In a way that never stops or slows down; without showing pity, mercy, or letting up.
From 'relentless,' which comes from 're-' (again) and 'lent' (past tense of 'lend'). 'Lent' evolved from Latin 'lentus' meaning 'slow' or 'yielding,' so 'relentless' means 'not yielding.'
Here's a weird linguistic fact: 'relentless' contains the word 'lent,' which comes from a Latin word meaning 'slow'—so 'relentless' literally means 'not slow,' which is exactly why it describes things that never stop pushing forward without mercy.
Complete word intelligence in one call. Free tier — 50 lookups/day.