Appeal to authority, argument from authority.

Of or relating to ad verecundiam.

In an ad verecundiam manner.

(informal) classified advertisement

(of an academic degree) Awarded by one institution to an alumnus of another. / Recognised by one institution on behalf of another.

(aviation) Initialism of automatic dependent surveillance - contract. (automated transmission of GPS location information from an aircraft via a contractual agreement with an ACARS provider)

Alternative spelling of value added

(economics, business) the amount by which the value of an article is increased at each stage of its production, exclusive of initial costs

(economics, business, of goods) having features added to a basic line or model for which the buyer is prepared to pay extra

plural of ad-libber