n (uncountable) The quality of being different.
n (countable) A characteristic of something that makes it different from something else.
n (countable) A disagreement or argument.
n (countable, uncountable) Significant change in or effect on a situation or state.
n (countable) The result of a subtraction; sometimes the absolute value of this result.
n (obsolete) Choice; preference.
n (heraldry) An addition to a coat of arms to distinguish two people's bearings which would otherwise be the same. See augmentation and cadency.
n (logic) The quality or attribute which is added to those of the genus to constitute a species; a differentia.
n (logic circuits) A Boolean operation which is true when the two input variables are different but is otherwise false; the XOR operation ( scriptstyle A◌̅B+◌̅AB).
n (relational algebra) The set of elements that are in one set but not another ( scriptstyle A◌̅B).