IPA: //ˌsuːdəˈnɪməsli//
KK: /sudəˈnɪməsli/
In a way that uses a false name or identity, often to conceal one's true identity.
The author published her novel pseudonymously to protect her privacy.
Pseudonymously → It is formed from "pseudo-" (from Greek "pseudes", meaning false) and "onym" (from Greek "onuma", meaning name) and the suffix "-ously" (meaning in a manner). The word describes the act of using a false name or alias in a manner that conceals one's true identity.
Think of 'false' ('pseudo-') and 'name' ('onym') to remember that 'pseudonymously' means using a false name.