と研toぐguと磨toぐgu
1.
To enhance the sharpness or smoothness of an object by abrasion, typically involving repeated rubbing against a harder surface.
2.
To cleanse or purify a substance by friction, often involving washing to remove impurities.
3.
To improve the appearance of an item, giving it a polished or refined finish through careful rubbing or treatment.
Example:
彼女はいつも人に対してやいばをといでいます。