to buy

medium (the material or empty space through which signals, waves or forces pass) / medium (a format for communicating or presenting information) / vector (carrier of a disease-causing agent)

(informal) Used to sign off a message/attribute a text.

part-time job, especially for students (as opposed to one's main occupation when it is only part time) / part-time worker

to sell

viral

Bibai (a city in Sorachi, Hokkaido prefecture, Japan)

biathlon

The Plum in the Golden Vase, a Ming dynasty novel

Kyūjitai form of 売価: selling price; sale price