The basic form of a word used as a dictionary headword.

The imprint upon the surface of a body of water that is made by a feeding trout, indicative by its form of the feeding behavior of the fish.

(linguistics) A synonymous but not identical, coexisting form (variation) of a word, such as an accepted alternative spelling.

simple past tense and past participle of return to form

present participle of return to form

(algebra) A linear combination of powers of an indeterminate (or products of powers of more than one indeterminate), with coefficients belonging to an integral domain or a field. (The indeterminate is thought of as an element extraneous to the set of coefficients, instead of as a variable element of it (as in the case of polynomial functions), just as, say, the square root of negative one is an element extraneous to the set of integers when it is adjoined to them to form the domain of Gaussian integers. The indeterminate forms a free commutative monoid, to which all powers of it belong, and the unity of it can also show up implicitly in the constant term of a polynomial form.)

(idiomatic) To take shape

(political science) The system by which a state or community is controlled, as for decision-making or choice of rulers.

(mathematics, number theory, algebra) A homogeneous polynomial of degree 2 in a given number of variables.

(mathematics) A form (expression) that does not use limits, implicitly or explicitly. / (mathematics) A differential form whose exterior derivative is zero.