noun ·Rare ·Advanced level

Definitions

Noun

1. 1
   The carboxylic acid 4-isobutylphenylacetic acid once used in the treatment of rheumatoid arthritis uncountable

Etymology

From i(so)bu(tyl) + -fenac (“phenyl acetate”).

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.