Simple Definition of prolong
: to make (something) last or continue for a longer time
Examples of prolong
Additives are used to prolong the shelf life of packaged food.
High interest rates were prolonging the recession.
Origin of prolong
Middle English, from Middle French prolonguer, from Late Latin prolongare, from Latin pro- forward + longus long
First Known Use: 15th century
Synonym Discussion of prolong
Seen and Heard
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