(transitive, intransitive) To consume (something solid or semi-solid, usually food) by putting it into the mouth and swallowing it.
At twilight in the summer there is never anybody to fear—man, woman, or cat—in the chambers and at that hour the mice come out. They do not eat parchment or foolscap or red tape, but they eat the luncheon crumbs.
(intransitive) To consume a meal.
2016, VOA Learning English (public domain)
I eat in the kitchen.
(intransitive, ergative) To be eaten.
1852, The New Monthly Magazine (page 310)
I don't know any quarter in England where you get such undeniable mutton—mutton that eats like mutton, instead of the nasty watery, stringy, turnipy stuff, neither mutton nor lamb, that other countries are inundated with.
1863, Sheridan Le Fanu, The House by the Churchyard
[…] dish him [the fish] with slices of oranges, barberries, grapes, gooseberries, and butter; and you will find that he eats deliriously either with farced pain or gammon pain.
(copulative, intransitive) To have a particular quality of diet; to be well-fed or underfed (typically as "eat healthy" or "eat good").
To use up.
(transitive) To destroy, consume, or use up.
His wretched estate is eaten up with mortgages.
(transitive, programming, informal) To consume (an exception, an event, etc.) so that other parts of the program do not receive it.
2005, Wallace B. McClure, Gregory A. Beamer, John J. Croft IV, Professional ADO.NET 2 (page 246)
A bigger problem, however, is that if you catch/eat an exception and do nothing with it, you are very likely introducing subtle bugs in your application that will be next to impossible to track down.
(transitive, informal, of a device) To damage, destroy, or fail to eject a removable part or an inserted object.
1991, Shane Black, The Last Boy Scout (movie)
No! There's a problem with the cassette player. Don't press fast forward or it eats the tape!
(transitive, informal, of a vending machine or similar device) To consume money (or other instruments of value, such as a token) deposited or inserted by a user, while failing to either provide the intended product or service, or return the payment.
1977, Nancy Dowd, Slap Shot (movie)
Hey! This stupid [soda vending] machine ate my quarter.
(transitive, informal) To cause (someone) to worry.
(transitive, business) To take the loss in a transaction.
1988, George Gallo, Midnight Run (movie)
I have to have him in court tomorrow, if he doesn't show up, I forfeit the bond and I have to eat the $300,000.
(transitive, slang) To be injured or killed by (something such as a firearm or its projectile), especially in the mouth.
1944, William Faulkner, Leigh Brackett, Jules Furthman, The Big Sleep (screenplay)
I risk my whole future, the hatred of the cops and Eddie Mars' gang. I dodge bullets and eat saps.
1997, A. A. Gill, "Diary" (in The Spectator, 1 November 1997):
Friends are only necessary in the ghastly country, where you have to have them, along with rubber boots and a barometer and secateurs, to put off bucolic idiocy, a wet brain, or eating the 12-bore.
2012, Kaya McLaren, How I Came to Sparkle Again: A Novel, St. Martin's Press (→ISBN):
Mike had been to other calls where someone had eaten a gun. He knew to expect teeth embedded in the ceiling and brains dripping off it.
2017, Edward W. Robertson, Stardust, Edward W. Robertson:
The animal was sweating and scared and MacAdams was surprised when they finished up without either of them eating a kick.
2018, Daniel Tomazic, Of Bullies and Men: Young Adult Fiction (→ISBN), page 18:
There was a resounding smacking noise and Georgy was sure Philip had just eaten a fist.
(transitive, intransitive) To corrode or erode.
(transitive, slang) To perform oral sex (on a person or body part).
(slang) To be very good, to rule, rock
(consume):consume, swallow; see also Thesaurus:eat
(cause to worry):bother, disturb, worry
(eat a meal):dine, breakfast, chow down, feed one's face, have one's breakfast/lunch/dinner/supper/tea, lunch
(perform oral sex on (a person)):eat out; see also Thesaurus:oral sex
From Middle Englishete, ate, æte, from Old Englishǣt(“food, eating”), from Proto-West Germanic*āt, from Proto-Germanic*ētą(“food, thing to eat”), from Proto-Indo-European*h₁ed-(“to eat”). Cognate with North Frisianad, it(“food”), GermanAas(“carrion”), Norwegianåt, Icelandicát(“food”).
(colloquial) Something to be eaten; a meal; a food item.