IPA: /ˈheɪstɪli/
KK: /ˈhæs.tɪ.li/
In a quick or rushed way, often without careful thought.
She hastily packed her bag before leaving for the airport.
Hastily → It is formed from "hasty" (from Old French *hastif*, meaning quick or swift) and the suffix "-ly" (meaning in a manner of). The word "hastily" means in a quick or swift manner.
Think of doing something in a 'quick' way ('hasty') — the '-ly' just means in that manner. So, when you act hastily, you are acting quickly.