adjective / verb
blunt
Having an edge or point that has lost sharpness.
The blunt pencil makes a thick gray mark.

Etymology
Middle English blunt meant dull or not sharp. Direct, tactless speech is a figurative extension; the word's deeper origin is uncertain.
In context
so dangerous working in the kitchen with a blunt knife you can cause so much damage working with a sharp knife is 10 times quicker more efficient
More examples
- Heavy use blunted the blade.
- Her apology helped blunt their anger.
- Fatigue blunted his concentration.
Forms
blunt · blunter · bluntest · blunts · blunted · blunting
bluntness noun — lack of a sharp edge or point