The condition of having distinct gill-bearing segments or the principle of segmentation in gill regions.
From 'branchiomere' + '-ism' (state or condition suffix). Describes the organizational principle of repeated, similar gill-bearing units in fish anatomy.
Branchiomerism reveals that fish bodies follow a modular design principle—repeat the same gill-unit pattern several times, then decorate it differently, and you get all fish diversity.
Complete word intelligence in one call. Free tier — 50 lookups/day.