A push from behind, as to one who is endeavoring to climb.

Something that helps, or adds power or effectiveness; assistance.

“The controversy gave a boost to the author's sales.”

(automotive engineering) A positive intake manifold pressure in cars with turbochargers or superchargers.

To lift or push from behind (one who is endeavoring to climb); to push up.

(by extension) To help or encourage (something) to increase or improve; to assist in overcoming obstacles.

“This campaign will boost your chances of winning the election.”

To steal.