# featherless biped

idiom

Source: https://englishreference.com/idiom/featherless-biped
Updated: 2026-08-10

## Meaning

A human being.

## Examples

- The philosopher famously defined a human as a featherless biped.
- Every featherless biped in this room needs to sign the visitor log.
- In his biology lecture, the professor jokingly referred to his students as featherless bipeds to illustrate an ancient definition.
- The science fiction writer described the alien's first encounter with a featherless biped to show how strange humans look to outsiders.
- While the ancient thinker sought to categorize life with precision, his description of man as a mere featherless biped remains a curious relic of early logic.

## Origin

From the dialogue *Statesman* by the philosopher Plato (427–347 B.C.E.), who sought a precise taxonomy for the human race. The Greek text records the necessity of dividing walking animals into bipeds and quadrupeds, noting that as humans shared the bipedal category with birds, a further distinction was required. The resulting classification divided the biped class into the feathered and the featherless. The phrase remains a testament to the classical urge to define humanity by what it lacks, rather than what it possesses.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.