Meter refers to 1) the pattern of beats in a measure of music, or 2) to the number of syllables per line in poetry and music. Most hymnals do not include time signatures in the music, and are more concerned with the second definition of meter. (For more on the first definition, see the page on measures and time signatures and the page on simple and compound meter on the musictheory.net site.)
Hymnals display the meter of a hymn or hymn tune (meter to which the text conforms) either as a series of numerals (e.g., 87.87), letters (e.g., C.M.), or a combination (e.g., 87.87.D).
The meter of the Advent hymn, “Come thou long-expected Jesus,” is 87.87.
There are 16 hymns in our Hymnal in 87.87 meter (see the Metrical Index beginning on page 815). Thirteen of them are designated Trochaic, since, as in the example above, the accent falls on odd-numbered syllables. The other three are identified as Iambic, since the accent falls on even-numbered syllables (e.g., “The King of love my shep-herd is . . .).
In English hymns, a very common metrical pattern is 86.86, which is neatly designated Common Meter (C.M.). Hymns in Common Meter include “O for a thousand tongues to sing,” “As pants the hart for cooling streams,” “While shepherds watched their flocks by night,” and “O God our help in ages past.”
The abbreviation C.M.D. means “Common Meter Doubled,” which is the same as 184.108.40.206, and thus is present in hymns with twice as many lines per stanza as Common Meter hymns. “It came upon the midnight clear,” “The Son of God goes forth to war,” and “O Jesus, crowned with all renown” are examples of C.M.D.
Even more common than Common Meter in our Hymnal is Long Meter, which is the same as 88.88. “Creator of the stars of night,” “Ride on! ride on in majesty,” and “When I survey the wondrous cross” are in Long Meter. Long Meter Doubled (L.M.D.) is relatively rare, but one of our parish’s favorite hymns, “I bind unto myself today,” boasts an L.M.D. badge (except for the tricky verse six, which is in 88.88, with a repeat).
The metrical quality of the sung poetry of hymns — with the regularity of the hymn’s heartbeat — gives it great musical power. But we also regularly sing music that could be described as non-metrical. Much of the music we call “chant” — whether Anglican chant, as in our favorite sequence hymn, the “Te Deum laudamus,” or in Gregorian chant and other plainsong — as in the propers that the choir chants every Sunday — is non-metrical. There is still a pulse in the music, but it is constantly changing, line by line. The pulse follows the words rendered in prose, not in evenly measured poetry.