To prolong is to make something last longer.(verb)
When you read the last few pages of a good book very slowly so you can enjoy reading it longer, this is an example of a time when you prolong the book.
See prolong in Webster's New World College Dictionary
Origin: ME prolongen < MFr prolonguer < LL prolongare < L pro-, forth + longus, long: see pro- & long
See prolong in American Heritage Dictionary 4
transitive verb pro·longed, pro·long·ing, pro·longs
Origin: Middle English prolongen
Origin: , from Old French prolonguer
Origin: , from Late Latin prōlongāre
Origin: : Latin prō-, forth; see pro-1
Origin: + Latin longus, long; see del-1 in Indo-European roots.
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