The term 'Contrary Prefix' refers to words that are used to indicate the OPPOSITE of something. The three crossword solutions for this term are 'ANTI' (4 letters), 'ODDLY' (5 letters), and 'MARY' (4 letters). 'ANTI' is a prefix derived from the Greek word 'antí', meaning 'AGAINST' or 'OPPOSITE'. 'ODDLY' is an adverb that means 'in an unusual or unexpected way'. 'MARY' is a prefix derived from the Latin word 'mala', meaning 'BAD' or 'EVIL'. All three of these words can be used to indicate the OPPOSITE of something.