IPA: //ʌnˈsiːsɪŋli//
KK: /ʌnˈsiːsɪŋli/
In a way that does not stop or pause; continuously without interruption.
She worked unceasingly to complete the project on time.
Unceasingly → It is formed from "un-" (meaning not) and "ceaseless" (from Old English "ceaseless", meaning without stopping) and the suffix "-ly" (meaning in a manner). The word "unceasingly" means in a manner that does not stop or is continuous.
Think of 'not' ('un-') stopping ('ceaseless') — that's why unceasingly means something that continues without stopping.