"Supplement" is a word in ENGLISH

The number of degrees which, if added to a specified
arc, make it 180¡; the quantity by which an arc or an angle falls short
of 180 degrees, or an arc falls short of a semicircle.

That which fills up, completes, or makes an addition
to, something already organized, arranged, or set apart; specifically,
a part added to, or issued as a continuation of, a book or paper, to
make good its deficiencies or correct its errors.

That which supplies a deficiency, or meets a want; a
store; a supply.

To fill up or supply by addition; to add something
to.