When the units of sense in a passage of poetry coincide with the verses, and the sense does not run on from one verse to another, the lines are said to be end-stopped. When the verse length does not match the length of the units of sense (clauses, sentences, whatever), the lines are said to be enjambed.

Eighteenth-century verse was most often end-stopped, as can be seen in this passage from Pope:

Nothing so true as what you once let fall,
"Most women have no characters at all."
Matter too soft a lasting mark to bear,
And best distinguished by black, brown, or fair.
Notice each verse seems to contain a complete idea. Here, as often in Pope, sentences are restricted to couplets. Now compare a heavily enjambed stanza from the Renaissance poet Henry Vaughan:
With that some cried, "Away!" Straight I
Obeyed, and led
Full east, a fair, fresh field could spy;
Some called it Jacob's bed,
A virgin soil which no
Rude feet ere trod,
Where, since he stepped there, only go
Prophets and friends of God.
Here there's no sense of resting after many of the verses — "Straight I" needs to be continued, as does "and led," "which no," and "only go."

From the Guide to Literary Terms by Jack Lynch.
Please send comments to Jack Lynch.
Note: This guide is still in the early stages of development.
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