Translation guide
The act of making something sharp, such as a blade or a pencil. In Japanese, the verb used depends on the object being sharpened.
To make a blade sharp by grinding or honing.
General verb for sharpening blades, especially knives. Also used for polishing rice.
包丁を研ぐ。
Sharpen a kitchen knife.
Alternate kanji for 研ぐ, specifically for sharpening on a whetstone. Less common in everyday writing.
Sharpen a sword.
To sharpen to a fine edge; also used metaphorically for sharpening one's senses or skills.
Sharpen one's senses.
To make a pencil point sharp using a sharpener or knife.
To sharpen a tool like a chisel or plane blade.
To improve or hone an ability, sense, or mental acuity.
To polish, refine, or improve a skill. Literally means to polish a surface, but widely used for skills.
Sharpen one's skills.
To sharpen to a fine edge; used for senses or mental focus.
To forge, train, or discipline. Used for physical or mental strengthening.
Use 研ぐ (とぐ) for blades (knives, swords, tools) and 削る (けずる) for pencils. Using the wrong verb sounds unnatural.
Sharpen a knife (unnatural, use 研ぐ)
The English word 'sharpening' cannot be directly translated as a single noun in most contexts. Use the appropriate verb phrase instead.
Sharpen a pencil with a pencil sharpener.
Sharpen one's nerves / be on high alert.
頭を鍛える。
Sharpen one's mind.