jack of all trades, master of none
Describes a person who dabbles in many skills but excels at none. A rare, literary term; compare 螻蛄才 (けらざい), which has a similar meaning.
See also: 螻蛄才
He is a jack of all trades and master of none; he can do a little of everything, but nothing thoroughly.
Formed from 螻蛄 “mole cricket” and 芸 “skill.” It alludes to the traditional 螻蛄の五能: the insect was said to possess five abilities while mastering none of them.