Boyd’s Bible Dictionary:

(five fold book). Greek name for the first five O. T. books, or books of Moses. Called Torah, “the law,” by Hebrews.

Concise Bible Dictionary:

The Greek name given to the first five books of the Old Testament, which are also called “the five books of Moses.” The many references to and quotations from them in other parts of the scripture, and allusions to them by Christ under the name of Moses, show plainly that Moses was the inspired writer of them, except of course the small portion that records his death and burial. See MOSES.