1 extend (an action, condition, etc.) in time or space.
2 lengthen the pronunciation of (a syllable etc.).
3 (as prolonged adj.) lengthy, esp. tediously so.
Derivatives:
prolongation n. prolongedly adv. prolonger n.
Etymology: ME f. OF prolonger & f. LL prolongare (as PRO-(1), longus long)
Useful english dictionary. 2012.