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quantitate vs. quantify

[kwon-ti-teyt] / ˈkwɒn tɪˌteɪt /

verb (used with object)

quantitated, quantitating
  1. to determine the quantity of, especially with precision.

[kwon-tuh-fahy] / ˈkwɒn təˌfaɪ /

verb (used with object)

quantifies, present (3rd person singular) quantified, past participle, past quantifying present participle
  1. to determine, indicate, or express the quantity of.

  2. Logic. to make explicit the quantity of (a proposition).

  3. to give quantity to (something regarded as having only quality).