What is "gainstrive"

Gainstrive \Gain"strive`\, v. t. & i. [See Again, and Strive.] To strive or struggle against; to withstand. [Obs.]
--Spenser.

vb. 1 (context obsolete transitive English) To strive against; to resist, oppose. (16th century) 2 (context obsolete intransitive English) To resist; to fight back. (16th century)