IPA: /ɪnˈɡreɪʃiˌeɪtɪŋli/
KK: /ɪnˈɡreɪʃiˌeɪtɪŋli/
In a way that is intended to gain favor or approval from others, often by being overly flattering or agreeable.
She smiled ingratiatingly at her boss, hoping to win a promotion.
Ingratiatingly → It is formed from "ingratiate" (from Latin "ingratiari", meaning to bring oneself into favor) and the adverbial suffix "-ly" (meaning in a manner of). The word "ingratiatingly" means in a manner that seeks to gain favor or approval.
Think of someone trying to 'bring themselves into favor' — that's what ingratiatingly means, doing something in a way to please others.