Twelfth″–sec′ond (?), n.(Physics) A unit for the measurement of small intervals of time, such that 1012 (ten trillion) of these units make one second.
Content
Rights and sources
Review source, license and attribution information for this content.
Content
Webster's Dictionary 1913
Webster's Revised Unabridged Dictionary, C. & G. Merriam Co., 1913.