ureameter

from The Century Dictionary.

• noun An apparatus for determining the amount of urea in the urine.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Physiol. Chem.) An apparatus for the determination of the amount of urea in urine, in which the nitrogen evolved by the action of certain reagents, on a given volume of urine, is collected and measured, and the urea calculated accordingly.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An apparatus for measuring the amount of urea in urine, based on the amount of nitrogen produced in certain reactions.