noun a portion; a fragment.
2. fraction ·noun the act of breaking, or state of being broken, especially by violence.
3. fraction ·noun one or more aliquot parts of a unit or whole number; an expression for a definite portion of a unit or magnitude.
4. fraction ·vt to separate by means of, or to subject to, fractional distillation or crystallization; to fractionate;
frequently used with out; as, to fraction out a certain grade of oil from pretroleum.