Wikipedia
In philately, a cut square is an imprinted stamp cut from an item of postal stationery such as a stamped envelope, postal card, letter sheet, letter card, aerogram or wrapper in a square or rectangular shape. An alternative use of the term is simply any stamp, from sheets or postal stationery, cut in a square or rectangular shape and not cut to shape.
It is distinguished from the entire (the complete postal stationery item) or the more common practice of earlier eras of cutting to shape by removing all of the paper apart from the imprinted stamp. A variant of the cut square is the full corner which is a cutting of the corner to include the intact flap and back of the envelope as well as the front.
Just as used postage stamps were cut out, soaked and placed in an album, collectors also cut out postal stationery indicia and mounted them conveniently in albums. Now, the practice is frowned upon by most collectors who collect the entire, thus saving the envelope's postal history, the knife of the envelope and the postmark. To illustrate how far things have shifted in emphasis from the collection of cut squares, the most recent UPSS publication on US 20th and 21st century stamped envelopes does not even mention cut squares, whereas its predecessor edition, just seven years earlier, devoted a section to their pricing.
The term cut square is differentiated from the term used on piece which denotes an adhesive stamp cut out in similar fashion from the original cover so as to preserve the entire postmark.
Usage examples of "cut square".
They wore sandals, golden breast-plates, and scanty silk shirts supported by gem-crusted girdles, and their black manes, cut square at their naked shoulders, were bound with silver circlets.
The flowing lines of the dress, cut square at the neck, bore no lace or frills, nothing to distract from its simple elegance.
He was spare, broad-shouldered, taut and precise of movement, with a pallid complexion and black hair cut square across his forehead and tied in a rope at the back of his head.
Despite shoulders nearly as broad as mine and short hair cut square across the back of her neck, she was clearly feminine.
You see her costume - the way the neckline of her dress is cut square, the sleeves.
A robe of serge with large sleeves, a large woollen veil, the guimpe which mounts to the chin cut square on the breast, the band which descends over their brow to their eyes,-- this is their dress.
The women wore their hair in a simpler fashion than the men, cut square across the eyes and long behind, and they wore nothing but kilts or aprons of rabbit fur or trade cloth.