To untie, unfasten, unwrap, or undo something that is tied, bound, or wrapped.
靴ひもの結び目をゆっくり解いてから歩いた。
I slowly untied the knot in my shoelace before walking.
古い包みを丁寧に解いたら、手紙が出てきた。
When I carefully unwrapped the old package, a letter came out.
あの縄の結びを解いてください。
Please untie that rope knot.
To unsew or unstitch — to remove stitches or seams, often for alterations or repair.
ドレスの袖の縫い目を解いて、幅を広げた。
I unstiched the dress's sleeve seam and widened it.
To solve or work out a problem, puzzle, or question; to find an answer or solution.
この数学の問題を解くのに一時間かかった。
It took me an hour to solve this math problem.
彼は謎を解くのが得意だ。
He's good at solving mysteries.
暗号を解くために専門家を呼んだ。
We called an expert to decipher the code.
試験でたくさんの問題を短時間で解かなければならない。
You have to solve many questions in a short time during the exam.
To dispel misunderstandings or suspicions; to clear something up so it is no longer confusing or doubtful.
誤解を解くために詳しい説明を行った。
He gave a detailed explanation to clear up the misunderstanding.
彼女の説明でみんなの疑いは解けた。
Her explanation dispelled everyone's doubts.
To dissolve or cancel a contract, lift a prohibition, or raise a siege — to remove a formal restriction or binding condition.
両者は合意のもとで契約を解いた。
The two parties dissolved the contract by mutual agreement.
敵軍は包囲を解き、町に平和が戻った。
The enemy lifted the siege, and peace returned to the town.
To relieve someone from duty or dismiss them from a post; to release someone from an obligation or assignment.
彼は不祥事のために職を解かれた。
He was relieved of his post because of the scandal.
事故後、当直から解かれて自宅待機になった。
After the accident he was relieved from duty and put on standby at home.
To comb out or card hair or fibers — to untangle and smooth hair or wool (usually written 梳く or said とかす).
毎朝ブラシで髪を梳くのが日課だ。
Brushing/combining my hair every morning is part of my routine.
羊毛を丁寧に梳いて糸にする。
Carefully card the wool to turn it into yarn.
もつれた毛先を指でとかしてからヘアオイルをつけた。
I untangled the knotted ends with my fingers before applying hair oil.