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That would be called a cryptid in case of the animal kingdom.cryptid

Some dictionariesdictionaries and encyclopediasencyclopediae define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

An animal whose existence or survival is disputed or unsubstantiated, such as the yeti.

Reification is yet anotherConspiracy theory

A conspiracy theory is the fear of a nonexistent conspiracy or the unnecessary assumption of conspiracy when other explanations are more probable. Evidence showing it to be false, or the absence of proof of the conspiracy, is interpreted by believers as evidence of its truth, thus insulating it from refutation

ApocryphalReification

Reification (also known as concretism, hypostatization, or the fallacy of misplaced concreteness) is a fallacy of ambiguity, when an abstraction (abstract belief or hypothetical construct) is treated as if it were a concrete real event or physical entity.

From Late Latin apocryphus (“secretIn other words, it is the error of treating something that is not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hiddenconcrete, obscure”such as an idea, thus “(books)as a concrete thing. A common case of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”)reification is the confusion of a model with reality: "the map is not the territory". Properly pluralReification is part of normal usage of natural language (the singular would be apocryphonjust like metonymy for instance), but commonly treated as well as of literature, where a collective singular. “Apocryphal” meaning “of doubtful authenticity”reified abstraction is first attested in Englishintended as a figure of speech, and actually understood as such. But the use of reification in 1590logical reasoning or rhetoric is misleading and usually regarded as a fallacy.

Old wife's taleApocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

An old wives' tale is a supposed truth which is actually spurious or a superstition. It can be said sometimes to be a type of urban legend, said to be passed down by older women to a younger generation. Such tales are considered superstition, folklore or unverified claims with exaggerated and/or inaccurate details. Old wives' tales often center on women's traditional concerns, such as pregnancy, puberty, social relations, health, herbalism and nutrition.

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Reification is yet another

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

cryptid

Some dictionaries and encyclopediae define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

An animal whose existence or survival is disputed or unsubstantiated, such as the yeti.

Conspiracy theory

A conspiracy theory is the fear of a nonexistent conspiracy or the unnecessary assumption of conspiracy when other explanations are more probable. Evidence showing it to be false, or the absence of proof of the conspiracy, is interpreted by believers as evidence of its truth, thus insulating it from refutation

Reification

Reification (also known as concretism, hypostatization, or the fallacy of misplaced concreteness) is a fallacy of ambiguity, when an abstraction (abstract belief or hypothetical construct) is treated as if it were a concrete real event or physical entity.

In other words, it is the error of treating something that is not concrete, such as an idea, as a concrete thing. A common case of reification is the confusion of a model with reality: "the map is not the territory". Reification is part of normal usage of natural language (just like metonymy for instance), as well as of literature, where a reified abstraction is intended as a figure of speech, and actually understood as such. But the use of reification in logical reasoning or rhetoric is misleading and usually regarded as a fallacy.

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

An old wives' tale is a supposed truth which is actually spurious or a superstition. It can be said sometimes to be a type of urban legend, said to be passed down by older women to a younger generation. Such tales are considered superstition, folklore or unverified claims with exaggerated and/or inaccurate details. Old wives' tales often center on women's traditional concerns, such as pregnancy, puberty, social relations, health, herbalism and nutrition.

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

3 added 30 characters in body
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That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Reification is yet another

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Reification is yet another

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

2 improved explanation
source | link

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated.

conspiracy theory could be another.

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

That would be called a cryptid in case of the animal kingdom.

Some dictionaries and encyclopedias define the term "cryptid" as an animal whose existence is unsubstantiated. (perfect example would be bigfoot)

conspiracy theory could be another.

Apocryphal

From Late Latin apocryphus (“secret, not approved for public reading”), from Ancient Greek ἀπόκρυφος (apókruphos, “hidden, obscure”, thus “(books) of unknown authorship”), from ἀπό (apó, “from”) + κρύπτω (krúptō, “I hide”). Properly plural (the singular would be apocryphon), but commonly treated as a collective singular. “Apocryphal” meaning “of doubtful authenticity” is first attested in English in 1590.

Old wife's tale

A supposed truth that has been passed down by word of mouth A rumour, myth or superstition; something which is almost certainly untrue, despite acceptance by many.

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