in Logic, denote two terms of a syllogism, the predicate and subject. They are called extremes, from their relation to another term, which is a medium or mean between them. The predicate, as being likewise contained in the first proposition, is called the major extremum or greater extreme; and the subject, as being put in the second or minor proposition, is called the minor extremum or lesser extreme. Thus, in the syllogism, "Man is an animal; Peter is a man; therefore Peter is an animal;" the word animal is the greater extreme, Peter the less extreme, and man the medium.

EXTREME and mean Proportion, in Geometry, is when a line is so divided, that the whole line is to the greater segment as that segment is to the other; or, as it is expressed by Euclid, when the line is so divided that the Extrinsic rectangle under the whole line, and the lesser segment, is equal to the square of the greater segment.