Synonymously

Part of speech: adverb

Definitions

1. In a way that conveys the notion of having the same meaning or being interchangeable in context
2. In a manner that signifies the equality of meaning between different expressions or terms
3. Done in a manner that shows two or more terms share the same meaning and can be used interchangeably

Etymology: "Synonymously" is simply "synonymous" with the adverbial ending "-ly" attached, and the adjective itself comes from Greek. "Synonymous" is built from "syn-", meaning "together" or "with", and "onyma", meaning "name", so the underlying idea is names that go together, or things called by the same name. The "-ly" ending has a long pedigree of its own: it descends from an old Germanic word meaning "body" or "form", which became "-līc" in Old English and gradually wore down into the "-ly" we use today. The adjective "synonymous" came into English from Late Latin "synonymus", which in turn was taken from Greek, and it was used to describe words with the same sense. The adverb is a plain formation on top of that adjective, so its story is mostly the story of the suffix it carries.