Definition (Adjective) Strictly observant of or insistent on fine points of procedure, etiquette, or conduct; extremely or excessively particular or correct. Also: characterized by such scrupulous attention to detail or formality. In Context "Spain, degenerate and fallen in many respects, is as punctilious and jealous of her honor as ever she was, and would not hesitate to declare war against the most powerful nation on earth in defense of the least valuable of her possessions." "Cuba and Central America," San Francisco Chronicle, June 21, 1873.