IPA: /ʌnˈɡæl.ənt.li/
KK: /ʌnˈɡælən(t)li/
In a manner that is not courteous or chivalrous, often showing a lack of respect or consideration for others.
He acted ungallantly by interrupting her speech without any apology.
Ungallantly → It is formed from "un-" (meaning not) and "gallant" (from Old French *galant*, meaning courteous or brave) and the suffix "-ly" (meaning in a manner). The word describes behavior that is not courteous or brave.
Think of 'not' ('un-') being combined with 'courteous' or 'brave' ('gallant') to remember that 'ungallantly' means behaving in a way that lacks courtesy or bravery.