A measure of rhythmic quantity, the organized succession of groups of syllables at basically regular intervals in a line of poetry, according to definite metrical patterns. In classic Greek and Latin versification, meter depended on the way long and short syllables were arranged to succeed one another, but in English the distinction is between accented and unaccented syllables. The unit of measure is the foot. Metrical lines are named for the type of constituent foot and for the number of feet in the line: monometer (1), dimeter (2), trimeter (3), tetrameter (4), pentameter (5), hexameter (6), heptameter (7) and octameter (8); thus, a line containing five iambic feet, for example, would be called iambic pentameter. Rarely does a metrical line exceed six feet.