an instrument that is used for removing hair by shaving 剃须刀；刮脸刀 
a disposable razor 一次性剃须刀
Extra ExamplesTopics Appearanceb2He slashed his wrists with a razor. 他用剃刀割伤了手腕。 We used a razor to cut the string. 我们用剃刀割断了绳子。
Oxford Collocations Dictionaryadjective- blunt
- cut-throat
- disposable
- …
- cut somebody/something with
- shave with
- slash somebody/something with
- …
- blade
- wire
- with a/the razor
Word OriginMiddle English: from Old French rasor, from raser ‘shave closely’, from Latin ras- ‘scraped’, from the verb radere.
Idioms
be on the razor’s edge | be on a razor edge
to be in a difficult situation where any mistake may be very dangerous 处于非常危险的困境；境况岌岌可危 Social workers operate on the razor’s edge. 社会工作者如履薄冰。