re ‧ lent ‧ less /rɪˈlentləs/ BrE AmE adjective
1 . strict, cruel, or determined, without ever stopping:
her relentless determination to succeed
a regime that was relentless in its persecution of dissidents
2 . something bad that is relentless continues without ever stopping or getting less severe SYN endless :
the relentless crying of a small baby
a family facing relentless financial problems
—relentlessly adverb :
He questioned her relentlessly.