This post discusses a number of idiomatic expressions that refer literally or figuratively to consuming food and include some form of the word eat.
To say that someone will eat someone else for breakfast is to convey that the first person will easily defeat the other in whatever competition or rivalry they are engaged in. Meanwhile, a dog-eat-dog environment is a highly competitive one, with a hyperbolic notion that people within it are so ruthless that they are like animals desperate enough to kill and eat each other. Similarly, to say that one person will eat another’s lunch is, on the analogy of the cliché of a child stealing a classmate’s lunch, to suggest that a competitor or rival will best someone else decisively. On a related note, “Eat one’s young” means to betray someone to whom one has a responsibility.
“Eat your heart out!” is a taunt to someone noted for an accomplishment, skill, or talent expressing that the speaker has outperformed the targeted person in that area; the idiom alludes to the notion that the target will agonize about being outperformed to the extent that it affects the person’s health—the defeat metaphorically eats away at his or her heart. Meanwhile, “Eat me!” and “Eat my shorts!” are vulgar taunts, while “Eat my dust!” from the notion that one will be running or driving faster, leaving the other person in a cloud of dust of one’s making, is milder to the point of being acceptable as a lighthearted jab.
To say that one is getting or having a bite to eat, or to invite someone to join one for a bite to eat (or just a “bite”), suggests that the food consumed will consist of a snack or a light meal, though in reality it may turn out to be a full meal. To eat and run is to dine hurriedly. When one says, “I hate to eat and run!” it’s generally a jocular apology about doing so. To eat in is simply to dine at home rather than going to a restaurant.
“Eat like a bird” alludes to how many birds pick at their food and seem to eat little, while “eat like a pig” invites comparison with the hearty enthusiasm of a pig when it eats. To eat one’s fill is to consume food until one is full, and a pregnant woman is said to be “eating for two” when her appetite increases. To eat someone out of house and home refers to when a house guest demonstrate one’s healthy appetite by exhausting the supply of food in the home of one’s host.
To say that one could eat a horse is to express that one is extremely hungry. (It’s unclear why this idiom specifies the horse, which in Western civilization has generally not been considered a source of meat for people except in dire circumstance, rather than another large animal associated with meat, such as a cow. One clue is that the expression appears in several sources as “so hungry, [one] could eat a horse behind the saddle,” alluding to a traveler being so desperate that he would kill his mount for food.)
When one says that one will eat one’s hat if something that seems unlikely is true or something that seems unlikely to happen occurs, the speaker is hyperbolically expressing that he or she will consume the headgear as punishment for his or her skepticism. The implication is that the speaker is so confident of the outcome that he or she believes that there is little chance he or she will have to keep his or her word and carry out the act.
By the same token, to eat one’s words is to figuratively ingest them after expressing something that has been challenged or refuted; the idea is the same as having to take back one’s words. Eating crow or eating dirt, similarly, refers to the humiliation of being proven wrong; the notion is of having to ingest something unpalatable. The idea of eating humble pie is a figurative extension.
When an idea, or an emotion such as guilt, eats away at someone, it is because the person feels as he or she is being gnawed at, with emotional distress akin to physical harm. By contrast, to say that something is eating through something else refers to one substance dissolving another, although it might also refer to pests such as termites gnawing on wood, and to say that one is being eaten alive is figurative and alludes to being swarmed by mosquitoes or biting insects.
To eat high off the hog is to live well and prosper, from the notion that the best cuts of pork are located on the upper part of the pig’s body.
To say that one has another person eating out of one’s hand (or the palm of one’s hand) suggests that the other person has been tamed, as when someone succeeds in getting a wild animal to eat food in this manner.
“Eat up!” is a friendly admonition to partake in a meal. “Eat, drink, and be merry” carries the same sentiment, although the original expression concluded fatalistically, “for tomorrow we die”—a comment uttered at a feast on the eve of battle.
When one is told that one looks good enough to eat, the speaker is comparing one’s attractiveness to the visual appeal of delicious-looking food. Meanwhile, assuring someone that one, or another person, “won’t eat you” is in response to the person assured being apprehensive about approaching or meeting someone because the other person seems imposing or threatening or the first person is shy.
“Let them eat cake” was supposedly a callous response by a member of royalty to a report that peasants were too poor to afford bread. However, it is wrongly attributed to Marie Antoinette, queen of France at the time of the French Revolution, who was reportedly generous to the indigent. A similar remark, referring to the crust of pâté rather than to cake, was rumored to have been uttered by another French queen more than a hundred years earlier and is likely the source of the misattributed quote.
To say that someone is mad enough to chew (or eat) nails suggests hyperbolically that the person is gnashing his or her teeth out of anger so passionately that he or she could easily gnaw through metal.
“Real men don’t eat quiche,” dating from the trendy popularity of the egg dish during the 1970s, suggests that the delicacy does not appeal to masculine taste in the way that, say, a piece of steak would.
To say that a room is so clean, one could eat off the floor hyperbolically concludes that it has undergone such a painstakingly thorough cleaning that the floor is safe for placing food on.
“You are what you eat,” originating early in the nineteenth century but repeated over the years and popularized during the 1960s, suggests the rather obvious notion that one’s diet determines the condition of one’s body. On a related note, the admonition to “eat your Wheaties” derives from the reputation of that brand of cereal for being particularly nutritious; one who wishes to be successful is encouraged to partake of it.
“You can’t have your cake and eat it, too” means that one cannot simultaneously continue to enjoy the fact that one possesses something while consuming it or using it up.
A reference to eating someone’s face has one of two meanings, depending on context. Denoting anger, it means that someone is so furiously confronting someone else that he or she is metaphorically devouring the other’s face. By contrast, people kissing passionately are sometimes said in humor to be eating each other’s faces.