relentlessly
adv.doing something in a way that never stops or gets weaker. You use this to describe someone who keeps trying very hard without giving up.
adv.in an unceasingly intense or harsh manner; without any decrease in strength or determination. Typically modifies verbs related to pursuit, criticism, or environmental conditions.
“The sun beat down relentlessly on the desert sand.”
“She worked relentlessly to finish the report before the deadline, refusing to take even a short break.”
“The investigative journalist pursued the lead relentlessly for months, eventually uncovering a web of corruption that reached the highest levels of the local government.”
Typically follows the verb it modifies or the direct object.
“In the relentlessly cruel and dangerous jungle, any distraction can be deadly.”
“Some farmers are being targeted so relentlessly and violently that they have become suicidal.”
From relentless + -ly.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.