Comparative form of germy; more contaminated with germs or containing more microorganisms.
From 'germy' (adjective meaning full of germs, from 'germ' + '-y' + comparative suffix '-er'). Informal adjective that became common in colloquial English during the 20th century.
Germier is hilariously informal—the scientific establishment uses 'more contaminated with microorganisms,' but germier is what parents actually say, showing how everyday speech resists formal terminology and carves its own efficient shortcuts.
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