(countable) A quantity of something that is part of the whole amount or number. / (uncountable) Harmonious relation of parts to each other or to the whole. / (countable) Proper or equal share.

(transitive) To divide into proper shares; to apportion. / (transitive) To form symmetrically. / (transitive, art) To set or render in proportion. / (transitive, archaic) To correspond to.

(law) The duty of a party in a legal proceeding to prove an assertion of fact; it includes both the burden of production and the burden of persuasion; the onus probandi.

(economics) The total market value of all the goods and services produced by a nation (citizens of a country, whether living at home or abroad) during a specified period.

(linear algebra) A vector product.

(linear algebra) The product of two vectors computed as the sum of the corresponding elements of the vectors, or, equivalently, as the product of the magnitudes of the vectors and the cosine of the angle between their directions.

(linear algebra) a vector with the size given by the product of two vectors computed as the product of the magnitudes of the vectors and the sine of the angle between their directions, and directed perpendicular to the given two vectors, with positive orientation.

(linear algebra) A scalar product.

A difficulty that has to be resolved or dealt with. / A question to be answered, schoolwork exercise. / A puzzling circumstance. / Objection.

(of a person or an animal) Difficult to train or guide; unruly. / Causing a problem; problematic; troublesome.