(chemistry) Any one of the simplest chemical substances that cannot be decomposed in a chemical reaction. Chemical elements consist of atoms which have the same number of protons.

(geology) An element which is not a trace element in a given context, and which is present in significant quantity.

(algebra) An element of an algebraic structure which when applied, in either order, to any other element via a binary operation yields the other element.

(chemistry) Any synthetic element having an atomic number greater than that of uranium.

(chemistry) A chemical element present in a sample in very small quantities.

(chemistry) Any of the group of metallic elements that have an incomplete inner (d) electron shell, having multiple valencies and forming coloured compounds and stable complex ions; the elements from scandium through copper, and those lying below them in the periodic table.

(linear algebra) An element on the main diagonal of a square matrix, that is, an element in row k and column k where k is an integer between 1 and the number of rows (or columns) in the matrix.

In a situation which is entirely suitable, familiar, or enjoyable.

(chemistry, geology) any chemical element which occurs in nature uncombined with other elements; includes the atmospheric gases, several metals and semimetals, and the nonmetals sulfur and carbon

An element that is used to make up an alloy.