1to stuff, cram, or pack items into a space so they fill it.
箱に本を詰める。
I pack books into the box.
冷蔵庫に食べ物をぎゅうぎゅうに詰めた。
I stuffed the fridge full of food.
スーツケースに服を詰めて旅行に出発した。
I packed clothes into the suitcase and left for the trip.
2to shorten (e.g., clothing), to move things or people closer together; to tighten a schedule.
ズボンの丈を詰めてもらった。
I had the hem of my pants shortened.
席を詰めて座ってください。
Please move over and sit closer together.
会議の時間を詰めて午後にまとめた。
We tightened the schedule and held the meeting in the afternoon.
3to reduce spending; to cut costs or conserve expenses.
来月の出費を詰めて貯金しよう。
I'll cut next month's expenses to save money.
旅行費用を詰めるために外食を控えた。
I cut back on eating out to reduce travel costs.
4to concentrate intensely on something; to apply oneself closely (often used as 根を詰める).
試験前は根を詰めて勉強した。
Before the exam I studied intensively.
彼はプロジェクトに根を詰めて取り組んでいる。
He is working on the project with intense focus.
5to go through details thoroughly; to work out particulars and bring something to a conclusion.
契約内容を詰めて、来週サインする予定だ。
We'll finalize the contract details and plan to sign next week.
会議で日程の細かいところを詰めた。
We worked out the fine points of the schedule in the meeting.
6to be on duty or stationed at a place; to be posted/assigned somewhere.
今夜は店に詰めている人が少ない。
There are few people on duty at the store tonight.
病室に看護師が詰めていた。
Nurses were stationed in the ward.
7to corner or trap (an opponent's king in shogi); to checkmate or close off escape routes.
角で相手の玉を詰める一手を指した。
I played a move that traps the opponent's king with a bishop.
8(1) to cut off one’s finger as an act of apology; (2) to catch or crush one’s finger (e.g., in a door) — the second sense is especially common in Kansai.
昔は侍が罪の責任として指を詰めることがあった。
In the past, samurai sometimes cut off a finger as a form of taking responsibility for a crime.
ドアに指を詰めてしまって、とても痛かった（関西でよく聞く表現）。
I caught my finger in the door and it hurt a lot (an expression often heard in Kansai).
9as an auxiliary verb, to do something continuously or without a break (～continuously).
彼は朝から晩まで働き詰めた。
He worked nonstop from morning until night.
10as an auxiliary verb, to do something completely or thoroughly (to finish something fully).
問題を考え詰めて、ついに解決策が見つかった。
After thinking the problem through thoroughly, a solution was finally found.
11as an auxiliary/transitive use, to press someone repeatedly with questions or actions so as to corner or force them into a difficult position.
記者は次々と質問を詰めて、真相を明らかにした。
Reporters pressed him with question after question and clarified the truth.