n. Tartness; sourness; sharpness.n. Keen or vehement desire in the pursuit or for the attainment of something, or a manifestation of such desire; ardent tendency; zeal; fervor: as, to pursue happiness or wealth with eagerness; eagerness of manner or speech.n. Synonyms Earnestness, Avidity, Eagerness, Zeal, Enthusiasm, ardor, vehemence, impetuosity, heartiness, longing, impatience. The first five words may all denote strong and worthy movements of feeling and purpose toward a desired object. In this field eagerness has either a physical or a moral application; with avidity the physical application is primary; earnestness, zeal, and enthusiasm have only the moral sense. Avidity represents a desire for food, primarily physical, figuratively mental: as, to read a new novel with avidity; it rarely goes beyond that degree of extension. Eagerness emphasizes an intense desire, generally for specific things, although it may stand also as a trait of character; it tends to produce corresponding keenness in the pursuit of its object. Earnestness denotes a more sober feeling, proceeding from reason, conviction of duty, or the less violent emotions, but likely to prove stronger and more permanent than any of the others. The word has at times a special reference to effort; it implies solidity, sincerity, energy, and conviction of the laudableness of the object sought; it is contrasted with eagerness in that it affects the whole character. Zeal is by derivation a bubbling up with heat; it is naturally, therefore, an active quality, passionate and yet generally sustained, an abiding ardor or fervent devotion in any unselfish cause. Enthusiasm is so far redeemed from its early suggestion of extravagance that it denotes presumably a trait of character more general than eagerness or zeal, more lively than earnestness, a lofty quickness of feeling and purpose in the pursuit of laudable things under the guidance of reason and conscience; thus it differs from zeal, which still generally implies a poorly balanced judgment.