caliberEnglishOxford American Thesauruscaliber noun 1 they could ill afford to lose a man of his caliber: quality, merit, distinction, character, worth, stature, excellence, superiority, eminence, preeminence; ability, expertise, talent, capability, capacity, proficiency, competence; gifts, endowments, strengths, qualifications. 2 if only they could play rugby of this caliber every week: standard, level, grade, quality. 3 the caliber of a gun: bore, diameter, gauge; size, measure.