1) an assembly
1a) a place of assembly: especially an assembly met to see games
1b) the place of contest, the arena or stadium
2) the assembly of the Greeks at their national games
2a) hence the contest for a prize at their games
2b) generally, any struggle or contest
2c) a battle
2d) an action at law, trial
Part of Speech: noun masculine
Citing in TDNT: 1:135, 20
From G71; properly a place of assembly (as if led), that is, (by implication) a contest (held there); figuratively an effort or anxiety: - conflict, contention, fight, race.
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root ἀγών; click on the second column to search for that grammatical form of the root ἀγών; click on the third column to search for that word and grammatical form; click on the total to search for the root ἀγών.