'antiradical' originates from Greek and Latin elements: the prefix 'anti-' (from Greek 'anti') meaning 'against' combined with 'radical' (from Latin 'radicalis', from 'radix') meaning 'root'.

'radical' comes from Latin 'radix' ("root"), passed into Late Latin as 'radicalis,' into French and then Middle English as 'radical.' The combining form 'anti-' (Greek 'anti') was attached in modern English to form 'antiradical,' and the adverbial suffix '-ly' produced 'antiradically.'

Initially, 'radical' meant 'of or relating to a root'; over time it developed senses of 'fundamental' and then 'thoroughgoing' or 'extreme' (especially politically). 'Antiradical' therefore came to mean 'opposed to radical (especially political) movements or changes,' and 'antiradically' means 'in a manner opposing radicalism.'