bird

\ \ [OE] Bird is something of a mystery word. It was not the ordinary Old English word for ‘feathered flying animal’; that was fowl. In Old English, bird meant specifically ‘young bird, nestling’. It did not begin to replace fowl as the general term until the 14th century, and the process took many hundreds of years to complete. Its source is quite unknown; it has no obvious relatives in the Germanic languages, or in any other Indo-European language.

\ \ The connotations of its original meaning have led to speculation that it is connected with breed and brood (the usual Old English form was brid, but the r and i subsequently became transposed in a process known as metathesis), but no convincing evidence for this has ever been advanced.

\ \ As early as 1300, bird was used for ‘girl’, but this was probably owing to confusion with another similar Middle English word, burde, which also meant ‘young woman’. The usage crops up from time to time in later centuries, clearly as an independent metaphorical application, but there does not really seem to be an unbroken chain of occurrences leading up to the sudden explosion in the use of bird for ‘young woman’ in the 20th century.

\ \ Of other figurative applications of the word, ‘audience disapproval’ (as in ‘get the bird’) comes from the hissing of geese, and in ‘prison sentence’ bird is short for bird lime, rhyming slang for time.