A requirement.
An urgent request.
The desire to purchase goods and services.
An order.
The amount of a good or service that consumers are willing to buy at a particular price.
A forceful claim for something.
More precisely peak demand or peak load, a measure of the maximum power load of a utility's customer over a short period of time; the power load integrated over a specified time interval.
To require of someone.
To claim a right to something.
To ask forcefully for information.
To request forcefully.
To issue a summons to court.
A necessity or prerequisite; something required or obligatory. Its adpositions are generally of in relation to who or what has given it, on in relation to whom or what it is given to, and for in relation to what is required.
Something asked.
A statement (in domain specific terms) which specifies a verifiable constraint on an implementation that it shall undeniably meet or (a) be deemed unacceptable, or (b) result in implementation failure, or (c) result in system failure.