The common rue.

Common rue (Ruta graveolens). / Bacopa monnieri.

(archaic, idiomatic) To go by the best possible route.

(set theory) One of the axioms in axiomatic set theory, equivalent to the statement that if two sets exist, there exists a set with those two sets as its sole elements.

(set theory) One of the axioms in axiomatic set theory that guarantees the existence of an infinite set.

(set theory) One of the axioms in axiomatic set theory, equivalent to the statement that a union exists for any set, containing exactly all the elements contained within the sets within that set.

The angle a balanced magnetic needle makes with the plane of the horizon, measured by the dipping needle, or compass.

The angle of the horizon below the level of the eye.

(set theory) One of the axioms in axiomatic set theory, equivalent to the statement that every non-empty set contains a member that is disjoint from that set.

(transitive, idiomatic, nonstandard) Synonym of blow out of proportion.