inofensivo
/inofenˈsibo/ · B2 · adj
harmless, innocuous
🐑 in- (not) + ofensivo (offensive) = not offensive, so harmless
It comes from Latin in- (not) + offendere (to strike or hurt). Something inofensivo doesn't strike anyone, so it's harmless. In Spanish, the English double f becomes a single f, and the -ive ending becomes -ivo.