The use of physical or mental energy to do something; exertion.
A difficult exertion of the strength or will: It was an effort to get up.
A usually earnest attempt: Make an effort to arrive promptly.
Something done or produced through exertion; an achievement: a play that was his finest effort.
Physics Force applied against inertia.
[Middle English, from Old French esfort, from esforcier, to force, exert, from Medieval Latin exfortiāre : Latin ex-, ex- + Latin fortis, strong; see bhergh-2 in Indo-European roots.] ef'fort·ful adj., ef'fort·ful·ly adv.