ounce¹ / ouns/ • n. 1. (abbr.: oz) a unit of weight of one sixteenth of a pound avoirdupois (approx. 28 grams). ∎  a unit of one twelfth of a pound troy or apothecaries' measure, equal to 480 grains (approx. 31 grams).2. a very small amount of something: Robin summoned up every ounce of strength.3. short for fluid ounce.ounce² • n. another term for snow leopard.

ounce a unit of weight of one sixteenth of a pound avoirdupois (approximately 28 grams); a unit of one twelfth of a pound troy or apothecaries' measure, equal to 480 grains (approximately 31 grams). Recorded from Middle English, the word comes via Old French from Latin uncia ‘twelfth part (of a pound or foot)’, also the base of inch.
an ounce of practice is worth a pound of precept proverbial saying, late 16th century, meaning that a small amount of practical assistance is worth more than a great deal of advice; the proverb is found in a number of forms juxtaposing elements of contrasted value.

ounce1 unit of weight. XIV. ME. unce — OF. unce (mod. once) = It. oncia, †onza :- L. uncia twelfth part of a pound or foot (cf. INCH1), f. ūnus ONE, prob. intended orig. to express a unit.

ounce2 †lynx XIII; mountain panther XVIII. — AN. *unce, OF. once, beside lonce (the l of which was taken for the def. art.), repr. Rom. *luncia, f. lynx, lync- LYNX.