From ago; properly, a place of assembly (as if led), i.e. (by implication) a contest (held there); figuratively, an effort or anxiety -- conflict, contention, fight, race.
see GREEK ago
1. a place of assembly (Homer, Iliad 7, 298; 18, 376); specifically, the place in which the Greeks assembled to celebrate solemn games (as the Pythian, the Olympian); hence,
2. a contest, of athletes, runners, charioteers. In a figurative sense,
a. in the phrase (used by the Greeks, see τρέχω, b.) τρέχειν τόν ἀγῶνα, Hebrews 12:1, that is to say 'Amid all hindrances let us exert ourselves to the utmost to attain to the goal of perfection set before the followers of Christ'; any struggle with dangers, annoyances, obstacles, standing in the way of faith, holiness, and a desire to spread the gospel: 1 Thessalonians 2:2; Philippians 1:30; 1 Timothy 6:12; 2 Timothy 4:7.
b. intense solicitude, anxiety: περί τίνος, Colossians 2:1 (cf. Euripides, Ph. 1350; Polybius 4, 56, 4). On the ethical use of figures borrowed from the Greek Games cf. Grimm on Wis. 4:1; (Howson, Metaphors of St. Paul, Essay iv.; Conyb. and Hows. Life and Epistles of St. Paul, chapter xx.; McClintock and Strong's Cyclopaedia