/ Thesaurus / A Synonyms of add in Find synonyms for: Noun1. circuit board, circuit card, board, card, plug-in, add-in, printed circuitusage: a printed circuit that can be inserted into expansion slots in a computer to increase the computer's capabilitiesWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: blanch Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language