pa·per·knife 
(pāpər-nīf′)
(pāpər-nīf′)n.
A thin dull knife used for opening sealed envelopes, slitting uncut pages of books, and creasing paper.
- beat all
- beat a retreat
- beat around/about the bush
- beat around the bush
- beatbox
- beatboxing
- beat brains
- beat brains out
- beaten
- beater
- beat/flog a dead horse
- Beat Generation
- beatific
- beatifically
- beatification
- beatify
- beating
- beat it
- beatitude
- beatnik
- beat off
- Beaton
- beat one's brains
- beat (one's) brains (out)
- beat one's brains out