to gain upon
Webster's Dictionary (GCIDE)
Gain \Gain\, v. i. To have or receive advantage or profit; to acquire gain; to grow rich; to advance in interest, health, or happiness; to make progress; as, the sick man gains daily. [1913 Webster]
Thou hast greedily gained of thy neighbors by extortion. --Ezek. xxii. 12. [1913 Webster]
Gaining twist, in rifled firearms, a twist of the grooves, which increases regularly from the breech to the muzzle.
To gain on or To gain upon. (a) To encroach on; as, the ocean gains on the land. (b) To obtain influence with. (c) To win ground upon; to move faster than, as in a race or contest. (d) To get the better of; to have the advantage of. [1913 Webster]
The English have not only gained upon the Venetians in the Levant, but have their cloth in Venice itself.— Addison.[1913 Webster]
My good behavior had so far gained on the emperor, that I began to conceive hopes of liberty.— Swift.[1913 Webster]