tablespoon

An unofficial unit of liquid and dry measure, = 3 teaspoons in the United states and 4 teaspoons in Britain. Currently, in both Britain and the United States, there are 16 tablespoons in a cup. In Britain, a cup contains 10 fluid ounces, and a tablespoon is ⁵⁄₈ ounce, approximately 17.75766 milliliters. In the United States, a tablespoon is ½ U.S. fluid ounce, approximately 14.786351 milliliters.

Most tablespoon measures sold today, largely for kitchen use, are marked 15 mL.

Chauncey Leake, a pharmacologist who became interested in ancient Egyptian medicine, remarks “I have examined many such [ancient Egyptian] spoons in archaeological museums, and they all hold between 14 and 15 milliliters.”¹ Very likely 14 to 17 mL is approximately the capacity of the largest container that fits comfortably into the human mouth.

An English pharmacopeia of 1618 described the tablespoon as the volume of distilled water weighing 3 drachms.

1. Chauncey D. Leake.
Standards of measurement and nursery rhymes.
in Systems of Units. National and International Aspects.
Carl F. Kayan, editor.
Publication No. 57 of the AAAS.
Washington, D. C.: American Association for the Advancement of Science, 1959.

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