/ Thesaurus / H Synonyms of hydrocyanic acid Find synonyms for: Noun1. hydrocyanic acid, prussic acid, acidusage: a solution of hydrogen cyanide in water; weak solutions are used in fumigating and in the synthesis of organic compoundsWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: cygnet Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language