To bind or secure papers/books together (e.g., with staples, thread, or a file).
この報告書を綴じて提出してください。
Please bind/file this report and submit it.
裁断した紙を糸で綴じて製本した。
I sewed the cut pages together to bind the book.
領収書はクリップで綴じて保管しておいてください。
Clip the receipts together and keep them.
In cooking, to finish a dish by pouring beaten egg into the broth or over ingredients so it sets (commonly written in kana as とじる).
親子丼は卵でとじて作る料理です。
Oyako-don is a dish finished by binding it with egg.
最後に溶き卵を回し入れて、ふんわりととじる。
At the end, pour in the beaten egg and lightly let it set.
かき玉汁は卵をとじて作る汁物の一つだ。
Kakitama-jiru is a kind of soup made by adding and setting egg.
Dated: to sew up or stitch together (used historically; uncommon today).
古い日記の破れた頁を綴じるのに時間がかかった。
It took time to stitch together the torn pages of the old diary.
布を綴じて傷口を保護した（文語的・古風な表現）。
He sewed the cloth up to protect the wound (literary/archaic expression).