METRE (jj.tr pitch, sc. r'exvr}, from Gr. i^rpov, measure), in prosody, the harmonious and regulated disposition of syllables into verse. Metrical form is distinguished from prose by the uniformity of corresponding lines in relation to the number of syllables and the similarity of final sound (rhyme or assonance), by the repetition of certain letters at regular intervals (in alliterative measure), or merely by the regular succession of ups and downs of intonation. In ancient classic poetry the measure which creates the metrical form consists only of this last quantitative element, which is rhythm.
For the rules and djvisions of the various metrical systems, see VERSE. For the restricted use of " metre " as a unit of measurement, see METRIC SYSTEM below.