Major, important.
Of or relating to an artery.
A through road.
Most; largest.
Most superior; most favorable.
Had best.
To surpass in skill or achievement.
To beat in a contest.
To the most advantage; with the most success, cause, profit, benefit, or propriety.
The person (or persons; or thing or things) that is (are) most excellent.
The supreme effort one can make, or has made.
One's best behavior.