IPA: /ˈwɜːrdləsli/
KK: /ˈwɜrdləsli/
In a way that does not involve speaking or using words.
She nodded wordlessly in agreement with his suggestion.
Wordlessly → It is formed from "word" (from Old English *word*, meaning a unit of language) and "-less" (meaning without) and "-ly" (meaning in a manner). The word "wordlessly" means in a manner without words or speech.
Think of being 'without' ('-less') 'words' ('word') — that's why wordlessly means doing something without speaking.