godan verb (-su), transitive verb
leave half-read; stop reading partway; leave unfinished
Used when one stops reading a book, article, etc. before finishing it. Often implies the reading is interrupted or abandoned temporarily.
その小説は長すぎて、途中で読みさしてしまった。
The novel was too long, so I left it half-read.
読みさし
A half-read book is lying on the desk.