mare's-nest

American  

[mairz-nest] / ˈmɛərzˌnɛst /

noun

1. something imagined to be an extraordinary discovery but proving to be a delusion or a hoax.

   The announced cure for the disease was merely another mare's-nest.

2. an extremely confused, entangled, or disordered place, situation, etc..

   We just moved in, and the place is a mare's-nest.

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mare's-nest British  

noun

1. a discovery imagined to be important but proving worthless

2. a disordered situation

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Etymology

Origin of mare's-nest

First recorded in 1610–20