Reference check
Calls to your former colleagues near the end of a process, usually to confirm what you've already said rather than to discover something new.
By the time references are requested, a decision has usually been made provisionally. The check is a verification step — dates, scope, how you worked with people — and it rarely reverses an outcome. It does occasionally, and the way it does is a contradiction: a reference describing a materially different role or tenure than your resume did.
Choose people who can speak to the specific thing this employer cares about, and brief them. Telling a reference which role you're up for, what you emphasized, and what they're likely to be asked isn't coaching them to lie — it's letting them give a useful answer instead of a vague one.
Many large employers only confirm dates and title through HR, so a former manager speaking personally is worth arranging in advance. And ask each reference for permission every time, not once; being called cold about a job someone didn't know you were pursuing produces a lukewarm call.
Interview loop
The set of interviews a company runs to make a decision — typically three to six sessions, each assigned a different signal to evaluate.
Offer letter
The written document stating the terms of employment — and the only version of the offer that binds anyone.