(informal, idiomatic) a (very) long time ago

(quantum mechanics) The general name for a vast category of physical problems pertaining to the properties of microscopic systems made of many interacting particles.

(chiefly Northern England, Scotland) A lot of small amounts, put together, become a large amount.

Alternative form of there's more than one way to skin a cat

(idiomatic) To try to fill more roles at once than is realistically possible.

Third-person singular simple present indicative form of wear too many hats

simple past tense of wear too many hats

present participle of wear too many hats

(idiomatic) Too many tasks, responsibilities, or details to cope with or manage successfully.

Wrong in many ways, to a great degree, or to the point of being disturbing.