used to form plurals of nouns of all three genders (e.g. заводи, жени, насекоми from masculine завод "factory", feminine жена "woman" and neuter насекомо...

(not a large amount of nouns, ending in -о) живо̀тно—живо̀тни насеко̀мо—насеко̀ми A change from the velar consonants к and х to ч and ш respectively око̀—очѝ...