The Proto-Indo-European word *h₁engʷ-
Word *h₁engʷ-
Meaning to swell
See also Proto-Indo-European: *negʷhrós ‘kidney’
Synonyms *bʰleu-, *pup-, teuh-, *bʰel-, *hₐeid-, k̂euh₁-

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