metric ounce

Noun

metric ounce (plural metric ounces)

1. 25 grams.
   • The new ounces would be all alike, representing 25 Gm. or CC., and would be from one-eighth to one-fifth less than the customary ounces. The metric ounce, 25.0; one fifth less than 1 apoth. ounce, 31.0. The metric ounce, 25.0, one-sixth less than 1 av. ounce, 28.35.1901, The Medical Standard, volume 24, page 306
   • It would probably be convenient also to retain the ounce, the metric ounce being defined as equal to 25 grams, or one-twentieth of the metric pound.1901 September 7, The Accountant, volume 27, number 1396, page 975
2. 30 grams.
   • Thirty grams or a metric ounce (the American ounce is 28 grams)1882, An Instruction Book in the Art of Silk Culture, page 83
   • If we could get the Post Office Department to adopt the metric system, so that whenever any citizen of the United States desires to send a letter he will have to buy postage stamps of one or two cents — whatever it might be — for 30 grams of matter, the metric ounce, that would give us a start.1890, Proceedings of the American Pharmaceutical Association