The opposite of literally is figuratively. We’d mostly use this word if there were a chance that something we said could be taken literally, or if we wanted to refer to both figurative and literal uses of the same phrase. For example:

Yet if the meanings of these two words are so diametrically opposed, why would people make apparently obvious mistakes with them? Here are some of the most egregious mistakes I’ve come across:

He’s literally on fire today! (football commentator describing a player’s impressive display)

I was literally gobsmacked! (celebrity-gossip reporter on a surprising story)

The first two are pretty obviously wrong: the player was not actually on fire, and no-one had actually smacked the reporter in the mouth (gob).

The other two are perhaps a little more debatable. The meaning of the sentence isn’t really changed by the girl saying she literally hates the pub. But here’s the thing: how many ways can you hate something? You either hate it or you don’t: saying you literally hate it doesn’t add anything as that’s the only way to hate something. You can’t figuratively hate something, wherein your hatred is a metaphor for something else. If she’s said I hate that pub the meaning wouldn’t change.

Literally is actually a very specific word, and we really only need to use it when we mean something literally, but there’s a chance that it could be taken figuratively. For example: we often say we’re speechless when we’re surprised, but don’t actually mean that we can’t speak. But you might find yourself in a situation so shocking that you actually can’t bring yourself to speak, and in this case you could say:

This emphasises the fact that you actually couldn’t speak. Or if you were so happy that you started jumping up and down, you could legitimately say that you were literally jumping for joy. But if something only has a literal meaning, there’s simply no need to use literally, as it doesn’t emphasise anything or clear anything up. It’s not as bad as using literally to mean figuratively, as in the first two examples above, but it adds unnecessary clutter to a sentence, and maybe even confuses listeners.

The last sentence is probably the most acceptable of the four, but I still think it’s much better without literally. Often when we say I’ll be there in five minutes, we’re not quite being exact in our timing, and might be a bit later than five minutes. When people say I’ll literally be there in five minutes or I’m literally five minutes away, they’re reassuring the other person that they won’t be late. Still, to use literally, they’d have to be exactly five minutes away, and how could they know that so precisely?

Why do people use literally when they don’t really need to then? In most cases, they’re using it for emphasis. That girl meant I really hate that pub! The Oxford English Dictionary also, regrettably, acknowledges this usage, though it does mark it as informal, at least:

informal Used for emphasis while not being literally true:

I think part of the reason people use it in this way is because of the sound of the word. Stressing that syllable with that hard /t/ sound at the end sounds quite emphatic, and can help to hammer your point home. And when literally is used correctly, it is often used for emphasis: only it’s specifically used to emphasise that something is to be taken literally, and not figuratively. Still, people unconsciously pick up on that emphatic usage, and it bleeds into their vocabulary, then becoming used for emphasis in all situations.

I still hesitate to say that that’s an acceptable use of the word, but I do understand where it comes from. That being said, there are still other words like really which work just as well, so why not just use them instead? I literally can’t imagine why people don’t.