用
Meaningsusebusinesspurposetask
How to remember
The kanji 用 originally depicted a bucket or a container, implying something that is 'used' or 'employed' for a specific 'purpose'. 'よう' — Imagine saying 'YO! What's the USE of that?' to remember the primary meaning and reading. Picture the inner square as a container or a tool, and the outer box as the object it is being USED on, or a 'purpose' it serves.