Oxford English Dictionary.
Form [< Latin forma, primarily shape, configuration]
I. Shape, arrangement of parts.
1.a. The visible aspect of a thing; now usually in narrower sense, shape, configuration, as distinguished from colour; occasionally, the shape or figure of the body as distinguished from the face.
4.Philosophy. a. In the Scholastic philosophy: The essential determinant principle of a thing; that which makes anything (matter) a determinate species or kind of being; the essential creative quality.This use of form (Aristotle's μορϕή or εἶδος) and matter (ὕλη) is a metaphorical extension of their popular use. In ordinary speech, a portion of matter, stuff, or material, becomes a ‘thing’ by virtue of having a particular ‘form’ or shape; by altering the form, the matter remaining unchanged, we make a new ‘thing’. This language, primarily applied only to objects of sense, was in philosophical use extended to objects of thought: every ‘thing’ or entity was viewed as consisting of two elements, its form by virtue of which it was different from, and its matter which it had in common with, others.
11. a. A set, customary, or prescribed way of doing anything; a set method of procedure according to rule (e.g. at law); formal procedure. a matter of form : a point of formal procedure; orig. a legal phrase; hence colloq. = a merely formal affair; a point of ordinary routine.
12.a. A set or fixed order of words (e.g. as used in religious ritual); the customary or legal method of drawing up a writing or document.
b. A formulary document with blanks for the insertion of particulars.