The Proto-Indo-European word *pipp-
Word *pipp-
Meaning young bird, nestling

Comments
Mallory J.P. and Adams D. (2006)

Other words that might be of interest
*ker-1, kor-, kr- ‘a kind of sound, crane, crow’, *kVr-C- ‘crow, raven’, *ĝhan-s ‘goose’, *hₐn̥hₐti- ‘duck’, *h₂ewi- (nom. h₂ewi-s, gen. h₂wei-s) ‘bird’, *h₃or-no- ‘eagle’, *k̂órw-eh₂- ‘crow’, *ĝhy-~ĝyei- ‘bird of prey, kite?’, *hₐewei- ‘bird’, *wer- ‘crow’, *k̂yeino- ‘bird of prey, kite’, *pad- ‘duck, teal?’, *(s)p(e)iko/ehₐ ‘bird, woodpecker’, *kap- ‘hawk, falcon’