Competing offer
Also called exploding offer, offer deadline.
A second live offer, which is the strongest and most honest source of leverage in a compensation conversation.
A real competing offer changes the conversation because it changes the employer's actual risk: they now face losing a candidate they've already decided to hire and restarting a process that cost them weeks. That's the mechanism, and it's why a genuine competing offer moves numbers that an argument about market data doesn't.
It only works if it's true. Recruiters talk, verification happens, and a bluff that unravels ends both processes. If you don't have one, the honest version — that you're at final stage elsewhere and would like to compare — is still useful and carries no risk.
Exploding offers, with a deadline short enough to prevent you finishing another process, are the counter-tactic. Asking for a specific extension with a reason usually gets one. A company that refuses any extension at all has told you something about how it treats people, and that's information worth having before you accept.
Offer letter
The written document stating the terms of employment — and the only version of the offer that binds anyone.
Pipeline
All the opportunities you have in progress at once, seen as a funnel from application through offer.
Total compensation
Everything an offer is worth in a year — base salary plus bonus, equity, and benefits — rather than the headline salary alone.