difficult / hard, probably impossible

slow, sluggish

dull (edge) / dull (sense), stupid

a Western knife, table knife

(obsolete) meat / (obsolete) flesh, as of one's body

letter opener, paper knife

utility knife; boxcutter

to cut, to slice, to carve / cut down, fell, chop down / prune, trim, shear / cut flat things such as cloth or paper / cut a person with a sword, cut down, kill

finish, be through / perform an action thoroughly or decisively

Yellowknife (a city in Canada)