'radiation-resistant' originates from Modern English, specifically the compound of 'radiation' and 'resistant', where 'radiation' ultimately comes from Latin 'radiatio' (from 'radiare') meaning 'to emit rays' and 'resistant' comes from Latin 'resistere' meaning 'to stand back or resist'.

'radiation' entered English via Medieval Latin 'radiatio' (from Latin 'radiare') and French influences; 'resistant' derives from Old French 'resister' and Latin 'resistere'; the two elements were combined in modern English to form the compound 'radiation-resistant'.

Initially, 'radiation' referred to the action or process of sending out rays and 'resistant' meant 'able to resist'; over time, the compound came to be used specifically for materials or devices 'able to withstand harmful effects of radiation'.