vesicant adjective 1noun 1forms 1 adjective1 •Causing blistering to the skin. noun1 •Any material that causes blisters upon contact with the skin.Rubber-clothed figures entered from an inner room like divers in air. Some of the vesicant-proof suits did not fit and the wearers moved uncomfortably and clumsily. — 1939 formsvesicants