Webster’s Revised Unabridged Dictionary · 1913 Labyrinthibranch Lab′y·rin′thi·branch (·thĭ·brăn̲k), a. [See Labyrinth, and Branchia.] (Zoöl.) Of or pertaining to the Labyrinthici. — n. One of the Labyrinthici. ‹ Labyrinthian Labyrinthic ›