Lyrics (in singular form lyric) are a set of words that make up a song, usually consisting of verses and choruses. The writer of lyrics is a lyricist or lyrist. The meaning of lyrics can either be explicit or implicit. Some lyrics are abstract, almost unintelligible, and, in such cases, their explication emphasizes form, articulation, meter, and symmetry of expression. The lyricist of traditional musical forms such as Opera is known as a librettist.