To reach out one's hand; to extend a hand toward something (literally reaching or touching).
テーブルの上のグラスに手を出してはいけないよ。
Don't reach out for the glass on the table.
赤ちゃんが危ないところに手を出そうとしたので、すぐに引きとめた。
The baby reached towards something dangerous, so I immediately pulled him back.
To get involved in something; to make a move on an affair or matter (often implies involvement where one perhaps shouldn't).
その危ない取引には手を出さないほうがいい。
You'd better not get involved in that risky deal.
彼女は副業に手を出して、仕事がおろそかになった。
She started taking on side jobs and her main work suffered.
親が余計に手を出すと、子どもの自立を妨げることがある。
If parents interfere too much, it can hinder their child's independence.
To strike or hit (with one's hand).
酔った男が突然彼に手を出したので、周りが止めに入った。
A drunk man suddenly struck him, so people around intervened to stop it.
喧嘩で先に手を出した方が悪いとされることが多い。
In fights, the person who throws the first punch is often considered at fault.
To steal or take (something) illicitly; to pilfer or grab (informal).
あの店員は客の財布に手を出していたという噂がある。
There are rumors that that clerk was stealing customers' wallets.
人の成果に手を出すのは許されない行為だ。
Taking credit for someone else's work is unacceptable.
To make a sexual advance or try to seduce someone; to lay hands on (colloquial, somewhat coarse).
酔った男性が店員に手を出したため、店から追い出された。
The drunk man made advances on the clerk and was kicked out of the shop.
そんな失礼なことに手を出すな。相手の気持ちを考えろ。
Don't do such disrespectful things. Consider the other person's feelings.