The term 'PREFIX WITH LINEAR' refers to THREE words that all have the same prefix, 'LINEAR, ' and each word has a different number of letters. The first word is 'RECTI, ' which has five letters. This word is derived from the Latin word 'rectus, ' meaning 'STRAIGHT.' The second word is 'TRI, ' which has THREE letters. This word is derived from the Greek word 'trias, ' meaning 'THREE.' The third word is 'MATRI, ' which has five letters. This word is derived from the Latin word 'mater, ' meaning 'mother.' All THREE words are related to the concept of linearity, as they all refer to something that is STRAIGHT, THREE-sided, or related to a mother figure.