Definition of "prolong"

prolong

/pɹəʊˈlɒŋ/

verb
third-person singular simple present prolongs, present participle prolonging, simple past and past participle prolonged
1. (transitive) To extend in space or length.
2. (transitive) To lengthen in time; to extend the duration of
  Quotations
  The departure was not unduly prolonged. In the road Mr. Love and the driver favoured the company with a brief chanty running. “Got it?—No, I ain't, 'old on,—Got it? Got it?—No, 'old on sir.”
  1922, Ben Travers, chapter 5, in A Cuckoo in the Nest
3. (transitive) To put off to a distant time; to postpone.
4. (intransitive) To become longer; lengthen.