spiral-bound

US /ˈspaɪ.rəl.baʊnd/
UK /ˈspaɪ.rəl.baʊnd/
"spiral-bound" picture
1.

bound with a spiral of wire or plastic passing through holes punched along one edge

:
The notebook was spiral-bound, making it easy to open flat.
She preferred spiral-bound calendars for their durability.