IPA: /ˈɡælɪŋli/
KK: /ˈɡælɪŋli/
In a way that causes annoyance or frustration.
She gallingly pointed out my mistakes during the meeting.
Gallingly → It is formed from "gall" (from Old English *gealla*, meaning bile or something bitter) and the suffix "-ingly" (meaning in a manner of). The word "gallingly" means in a manner that is bitter or irritating.
Think of something that is 'bitter' ('gall') and how it can be done 'in a manner' ('-ingly') that irritates you.