The property of being affirmative.

(historical) Of or pertaining to travel methodology. / (ecology, rare) Not endemic; found both inside a particular region and outside it (regardless of origin).

(trigonometry) The area hyperbolic tangent function, i.e., the inverse hyperbolic tangent function.

(topology, of a subset of a topological space) Given a subset S of a topological space X, a point x whose every neighborhood contains at least one point distinct from x that belongs to S.