modificationn.[L. modificatio a measuring: cf. F. modification. See Modify.]1. The act of modifying, or the state of being modified; a change; as, the modification of an opinion, or of a machine.(Bentley.)2. Something which has been modified; a modified form or condition; state as modified; as, the various modifications of light; the latest modification of the operating system crashes less frequently.()3. (Gram.) The alteration of the meaning of a word or phrase by another word or phrase; -- usually a restriction of the scope of the word modified; as, in the phrase a billion dollars is a relatively small sum to spend on cancer research the modification of small by relatively is needed to make the sentence accurate, rather than ludicrous.()