Answer: honing

AnswerCrossword Clue
HONING

Making dull knives sharper

HONING

Refining, as one's skills

HONING

Giving an edge to

HONING
Using a whetstone
HONING
Improving, in a way
HONINGSharpening
HONINGFunction of a strop.
HONINGSharpening.
HONINGImproving the edge
HONINGPerfecting
HONINGFine-tuning