The metre of a tune means the number of syllables the tune has in each line.

For example read:

'Mary had a little lamb'

This has 7 syllables

Ma-ry had a lit-tle lamb

The whole poem:

Mary had a little lamb

Its fleece was white as snow

and everywhere that Mary went

The lamb was sure to go

Would have a metre of  7687

This is useful as if you know the metre of a tune and of a poem you can

work out if the can be used together. Some of the

word of the songs in this site will fit to other tunes

as long as the metre is correct.