aliquot

from The American Heritage® Dictionary of the English Language, 5th Edition.

• adjective Of, relating to, or denoting an exact divisor or factor of a quantity, especially of an integer.
• noun An aliquot part.

from The Century Dictionary.

• Forming an exact measure of something: applied to a part of a number or quantity which will measure it without a remainder: thus, 5 is an aliquot part of 15.
• noun That which forms an exact measure; an aliquot part: as, 4 is an aliquot of 12.
• To divide into equal parts which are a multiple or a submultiple of another quantity.

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

• adjective (Math.) An aliquot part of a number or quantity is one which will divide it without a remainder. Opposed to aliquant.

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

• adjective Contained in the whole an integral number of times;
• noun chemistry, biotechnology a portion of a total amount of a solution or suspension.
• verb slang, chemistry, biotechnology, transitive to separate a volume of solution or suspension into aliquots.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun an integer that is an exact divisor of some quantity
• adjective signifying an exact divisor or factor of a quantity