UMBONIC is a playable word

umbo Scrabble® Dictionary

noun
pl. umbos or umbones
the rounded elevation at the center of a shield
(adjective) umbonal, umbonate, umbonic
57 Playable Words can be made from "UMBONIC"
   2-Letter Words (13 found)
   3-Letter Words (23 found)
   4-Letter Words (11 found)
   5-Letter Words (6 found)
   6-Letter Words (3 found)
   7-Letter Words (1 found)