A deadbolt is a strong lock on a door.

A deadbolt is a strong lock on a doorDeadbolt是裝在門上的一種堅固的鎖。

Inside it is a solid metal bar, the bolt, that slides into the door frame when you turn a key or a small knob.

Inside it is a solid metal bar裡面有一根實心的金屬條, the bolt就是bolt插銷, that slides into the door frame它會滑進門框裡 when you turn a key or a small knob當你轉動鑰匙或一個小旋鈕的時候。

The spring lock that clicks when you pull a door shut is easier to push back; a deadbolt does not spring. You have to turn it, and then it sits there, which is why it is harder to kick the door in.

The spring lock that clicks when you pull a door shut那種你把門帶上時會喀一聲的彈簧鎖 is easier to push back比較容易被推回去; a deadbolt does not springdeadbolt沒有彈性。 You have to turn it你得轉動它, and then it sits there然後它就固定在那裡, which is why it is harder to kick the door in這就是為什麼比較難把門踹開。

That is the “dead” part: not “broken,” and not “someone died,” but “not springy — fully thrown and still.” Many front doors have both a light latch and a deadbolt; people who care about safety turn the deadbolt at night.

That is the “dead” part這就是「dead」這個部分的意思: not “broken,”不是「壞掉」, and not “someone died,”也不是「有人死了」, but “not springy — fully thrown and still.”而是「沒有彈性──完全推到底，靜止不動」。 Many front doors have both a light latch and a deadbolt很多前門同時有一個輕的門閂和一個deadbolt; people who care about safety turn the deadbolt at night注重安全的人晚上會把deadbolt轉上。

You can also use it as a verb: to deadbolt the door.

You can also use it as a verb你也可以把它當動詞用: to deadbolt the doorto deadbolt the door把門上deadbolt鎖。

It is ordinary home English, a little technical if you are in a lock shop, not slang.

It is ordinary home English這是日常居家會用的英文, a little technical if you are in a lock shop在鎖具店裡會稍微專業一點, not slang但不是俚語。