startup (Noun) — A new business.
startup (Noun) — The act of setting in operation. ex. "repeated shutdowns and startups are expensive"
startup (Noun) — The act of starting a new operation or practice. ex. "the startup of the new factory was delayed by strikes"
startup (Verb) — Get going or set in motion. ex. "start up the computer"
startup (Verb) — Get off the ground. ex. "Who started up this company?"