Definition of "borer"

borer

/ˈbɔːɹə/

noun
plural borers
1. A tool used for drilling.
2. (MLE, slang) A knife fit for a stabbing.
3. A person who bores or drills; a person employed to drill bore holes.
4. A tedious person, who bores others; a bore.
  Quotations
  The boree has been heard from frequently since the Renaissance, and his sentiments have undergone little change. The borer hasn't had much to say for himself.
  1896, Harry Persons Taber, ‎Elbert Hubbard, The Philistine (volume 3, page 21)
  Rennie was an expert on boredom, having done a piece on it for Pandora's “Relationships” column in which she claimed that there were two people involved in boredom, not just one: the borer and the boree.
  2012, Margaret Atwood, Bodily Harm
5. An insect or insect larva that bores into wood.
6. One of the many types of mollusc that bore into soft rock.
7. A cyclostome, such as a hagfish, which bores into injured, dead, or decaying sea creatures to feed on their flesh.