bats

American  

[bats] / bæts /

adjective

Slang.

1. insane; crazy.

   He's gone bats.

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bats British  

/ bæts /

adjective

1. informal crazy; very eccentric

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Etymology

Origin of bats

First recorded in 1915–20; see origin at bat ², -s ³

Example Sentences

First identified in 1976 and believed to have originated in bats, Ebola is a deadly viral disease spread through direct contact with bodily fluids.

From Barron's • May 19, 2026

Scientists believe African fruit bats may be the source of the viruses that cause Ebola, according to the CDC.

From The Wall Street Journal • May 18, 2026

UCLA’s bats backed up Tinsley, with Bri Alejandre hitting a two-run home run to give the Bruins a 2-1 lead in the second inning.

From Los Angeles Times • May 17, 2026

An infection with Bundibugyo virus can occur when someone comes in contact with infected bats or primates, according to the WHO.

From MarketWatch • May 17, 2026

The thin piping of bats, the careless crashing of a waddling skunk, the underground bustle of voles, the distant calls of owls—all these sounds told him he was not hunting alone.

From "Pax" by Sara Pennypacker