Meaning of -S in English

I. noun plural suffix Etymology: Middle English -es, ~, from Old English -as, nominative & accusative plural ending of some masculine nouns; akin to Old Saxon -os see: -es II. adverb suffix Etymology: Middle English -es, ~, plural ending of nouns, from -es, genitive singular ending of nouns (functioning adverbially), from Old English -es — used to form adverbs denoting usual or repeated action or state III. verb suffix see: -est see: -es

Merriam Webster. Explanatory English dictionary Merriam Webster.      Толковый словарь английского языка Мерриам-Уэбстер.