Webster's Revised Unabridged Dictionary · 1913

Boost

Boost (bost) , transitive verb

[Compare Boast, v. i.]

To lift or push from behind (one who is endeavoring to climb); to push up; hence, to assist in overcoming obstacles, or in making advancement. [Colloquial United States]

Boost (bost) , noun

A push from behind, as to one who is endeavoring to climb; help. [Colloquial United States]