Nuts and Bolts: accentual verse.

Hickory dickory dock
The mouse ran up the clock
The clock struck one, the mouse ran down,
Hickory dickory dock.

[It might be worth pointing out here, for readers for whom English is not the first language, that hickory and dickory are basically sounds without meaning.]

There are lots of ways of getting verse to stick together, from using words that are similar to each other in some way (rhyme or alliteration for example) to arranging words so they play out a rhythm.

Accentual verse uses rhythm to stick itself together. For centuries it was fashionable in English serious verse to arrange each syllable so the verse walked along on what are called feet (a foot, in this case, being an arrangement of loud and quiet syllables. The word bother, for instance, has a loud syllable followed by a quiet one; in a line of verse the normal thing was to have a sequence of similar feet (in the case of bother loud-quiet) all in a row: Bother bother bother stupid scansion! That sort of thing.

Accentual verse uses the same idea, but much more freely. The verse Hickory dickory dock has basically two heavy stresses per line: 

HICKory dickory DOCK
The MOUSE ran up the CLOCK
The CLOCK struck one, the MOUSE ran down,
HICKory dickory DOCK.

This sort of thing is very useful if you're planning to dance a baby about to the verse, or skip to it. (It doesn't matter how many quiet syllables there are between the loud ones.)

The history of accentual verse runs from the earliest English verse (Beowulf, for example) to modern rap. It often uses other devices, too, not just the heavily stressed syllables. There'll often be a break in the middle of a line, or rhymes, or repeated sounds.

But it's wonderful to think of the form stretching all the way from Baa Baa Black Sheep to the Beastie Boys.

Word to Use Today: accent. This word comes from French, from the Latin accentus, from cantus, which means chant or song, which is a translation of the Greek prosōidia, which can be either a song sung to music, or the tone of a syllable.