n.[C]

1. 闩；门闩；窗闩
   The repairman installed an iron latch on the door.

   修理工在门上安了铁门闩。

2. 碰锁，弹簧锁

vt.

1. 用闩把……闩上；用碰锁把……锁上
   Don't forget to latch the door before you go to bed.

   睡觉前别忘了闩门。

vi.

1. 闩上；用碰锁锁上

vi.

1. 抓住；占有；理解[（+onto/upon）]
   John was very lucky to have latched onto the office with a river view.

   约翰非常幸运，占了一间能看到河的办公室。

n.

1. a bar with a catch and lever used for fastening a door or gate.
2. a spring lock for an outer door, which catches when the door is closed and can only be opened from the outside with a key.
3. Electronics  a circuit which retains whatever output state results from a momentary input signal until reset by another signal.

v.

1. fasten with a latch.
2. Electronics  (of a device) become fixed in a particular state.
3. (latch on) informal understand the meaning of something.
4. (latch on to) informal attach oneself to (someone) as a constant companion.
   ▸take up (an idea or trend) enthusiastically.
5. (latch on) (of a breastfeeding baby) manage to get its mouth into the correct position around the nipple.