(of a door or gate) closed but not locked（門）關(guān)著但沒鎖上
latch on
(of a breastfeeding baby) manage to get its mouth into the correct position around the nipple（哺乳嬰兒）用嘴叼到乳頭
latch on to informal 非正式
attach oneself to (someone) as a constant and usually unwelcome companion糾纏understand the meaning of (something)理解，明白
latch on to 或 latch onto
To get hold of; obtain取得；得到
柯林斯高階英漢雙解學(xué)習(xí)詞典釋義
N-COUNT
門閂；插銷
A latch is a fastening on a door or gate. It consists of a metal bar which you lift in order to open the door.
例句
You left the latch off the gate and the dog escaped.你沒把門閂插上，所以狗跑了。
N-COUNT
碰鎖；彈簧鎖
A latch is a lock on a door which locks automatically when you shut the door, so that you need a key in order to open it from the outside.
例句
...a key clicked in the latch of the front door.鑰匙插進(jìn)前門彈簧鎖里發(fā)出咔嗒一聲
VERB
用閂閂上；用碰鎖鎖上
If you latch a door or gate, you fasten it by means of a latch.
例句
He latched the door, tested it, and turned around to speak to Frank.他把門鎖上，又試了試，然后轉(zhuǎn)身和弗蘭克說話。
英漢詞典釋義
n.
(門窗的)門閂
To open the gate, lift up the latch.要打開大門, 先把門閂提起來。
vt. & vi.
用碰鎖鎖上(門等);閂上(門等)
Remember to latch the gate behind you.記住出門時(shí)把大門閂上。
糾纏，纏住(某人)
He latched onto us and we couldn’t get rid of him.他纏著我們，甩也甩不掉。
附著(在某物上)
The virus latches onto the red blood cells.這種病毒附著在紅細(xì)胞上。
對…產(chǎn)生興趣(并加以利用)
The government have latched onto environmental issues to win votes.政府已開始大談環(huán)境問題以爭取選票。They have a reputation for latching onto all the latest crazes.大家都知道他們對所有的最新時(shí)尚都有興趣。Young children latch onto phrases and repeat them over and over.小孩子喜歡成語，一遍遍地重復(fù)。
理解，懂得，領(lǐng)會(huì)(想法或某人的話等)
It took him a while to latch onto their style of humour.他過了一會(huì)兒才明白他們的幽默方式。She soon latched onto the idea.她很快就理解了這個(gè)想法。It was a difficult concept to grasp, but Sam latched on very quickly.那是個(gè)難掌握的概念，但薩姆很快就理解了。
英英詞典釋義
Noun
1. spring-loaded doorlock that can only be opened from the outside with a key
2. catch for fastening a door or gate; a bar that can be lowered or slid into a groove