no obj.
1- draw up air audibly through the nose to detect a smell, to stop it running, or to express contempt（出声地）吸气嗅, 吸鼻子; 嗤笑：
his dog sniffed at my trousers
他的狗嗅了嗅我的裤子
with direct speech 'You're behaving in an unladylike fashion, ' sniffed Mother.“你的行为不像淑女,"母亲嗤笑道。
1.1
- with obj. draw in (a scent, substance, or air) through the nose用鼻子吸（气味, 东西, 空气）。
1.2
- usu. with negative
sniff at
show contempt or dislike for嗤之以鼻, 蔑视： the price is not to be sniffed at.
价格很是不菲。
1.3
sniff around/round
informal investigate covertly, especially in an attempt to find out confidential or incriminating information about someone〈非正式〉暗中侦察（试图发现有关某人秘密或有牵连的信息）。
1.4
- with obj.
sniff something out
informal discover something by investigation〈非正式〉调查到： he made millions sniffing out tax loopholes for companies.
他通过发现税则漏洞帮公司赚了几百万。
1
- an act or sound of drawing air through the nose吸气：
he gave a sniff of disapproval.
他嗤了一声, 表示不同意。
1.1
- an amount of air or other substance taken up in such a way吸入的空气（或其他物质）：
his drug use was confined to a sniff of amyl nitrite.
他用药只限于小小一嗅亚硝酸戊脂。
1.2
- in sing. informal a hint or sign〈非正式〉线索, 迹象：
they're off at the first sniff of trouble.
他们一嗅到有麻烦就跑了。
1.3
- in sing. informal a small chance〈非正式〉一线希望：
the Olympic hosts will at least get a sniff at a medal.
奥运会东道主至少会有一丝希望拿到一块奖牌。
词源
Middle English: imitative.