I can usually tell someone is Australian (or maybe NZer) if they use the word ‘whinge’. Other nationalities don’t usually use this word.
- Bubba.
Also “myself” instead of “me” is an Irish thing.
Some more things that give Americans away to me:
“I wrote him” (“I wrote to him”)
“I visited with him” (“I visited him”)
“It will likely be…” (“It is likely to be…”)
“U SUXXXX I RUUUUULE” (“I’m jolly annoyed with you”)
Oh we “whinge” in Britain too. Famous for it, actually. 
Oh, another one is “protest”. In Britain, the accused might reasonably “protest his/her innocence” but if objecting to a new law or whatever , we protest **against it.
And I would say that in Britain we differentiate more between “in” and into". (Trying to think of example).
Ah - “Hello, come in the chatroom” seems quite different to me from “Hello, come into the chatroom”>
I tend to think that the UK, Australia and NZ are a sort of slang/spelling bloc. I know I use quite a few British terms, because of my background.
If Aussies and Kiwis were to fully break out here with regional slang, though, we wouldn’t be understod by most, IMHO.
Kyla, you might have HEARD it outside Ireland, but here’s where it comes from.
Straight translation from the Irish language.
Sorry, that was my very lame attempt at a joke. You can go 5 years without hearing ‘rubbish’ around here. It’s the only word I could think of from M.P., etc. Wanker. 
If it doesn’t say on my location thing; I’m Australian.
I’m pretty conservative with my word usage. I don’t go about calling people “mate” or “cobber” or “digger” or something ridiculous like that. I use “whilst” but just because I like using archaic sounding words. Whilst (:)) we use british spelling “pants” is pretty much entrenched here for two legged things you put on your legs. Actually, on a completely unrelated note, I was amused to hear “striped” pronounced as two syllables in “MacArthur Park”. Well, slightly less amused than at the rest of the lyrics, but it was still funny. Does anyone else do that, or was it just a lyrical device to stretch out the line?
Americans tend to say “oregano” as “oREGano” whilst (love that word…) non-americans tend to say “oreGAHno”. But that’s not the sort of thing you’d catch from reading text.
The “I wrote him” has always jarred in my mind, but then, why would it be any different from “I phoned him”?
Some obvious ones no-one’s pointed out would be for Americans to say “aluminum” or, like with the removing the “oe” from Greek words (which Australia tends to do, too, in my experience) to remove the “ae” from words like “paediatrician” or “paedophile” (Which I assume is Greek, too, because “ph” isn’t exactly found commonly in Latin.)
I love threads like these. I’m obsessed with the way people talk.
I’ve noticed that many British speakers/typers will tend to use phrases like “bit of a __” followed by a noun where Americans are more likely to use a phrase like “sort of” or “kind of” followed by an adjective. People from some parts of the UK are more likely to say “bugger this” or “bugger off” than the standard American “fuck this” and “fuck off”. Though ‘bloody’ has started being used by some Americans, I’ve noticed an angry American is more likely to use “fucking” as a modifier, like “this fucking stupid thing” and a Brit would use “this bloody stupid thing”. Keeping with this vulgarity motif is the ‘e’ on ‘shite’, which most Americans would only use to imitate a British speaker.
‘Er’ instead of ‘um’ seems very British, while ‘uh’ seems strictly American. Contractions like “alright” and “alot” seem American too.
Then there’s slang, or maybe not so much slang as idiom. “Good on you” (usually spelled ‘ya’) is Australian, but I’ve seen it used by non-Australians as well. (I’ve used it before, and I’m American. I just like the sound of it.) “Phone” instead of “call” seems British. I’ve never heard an American say “I phoned him”. Then there’s the definite articles: Americans are in the hospital while Brits are just in hospital. “Ill” is sometimes used by Brits where Americans would use “injured”-
American: “She was badly injured in a car accident and is in the hospital.”
Brit: “She was in a road accident and is very ill in hospital.”
“Sick” to a Brit usually means “sick to (or at) the stomach”, or nauseated, while to an American it can just mean the person has a cold.
Again, “a bit” instead of “a little” sounds British. Brits will also say “give us” instead of “give me”, or informally, “g’izz” instead of “gimme”. They also have a tendency to use plural possessive pronouns for family members: “our dad” as opposed to “my dad”. Then there’s the whole mum/mom divergence. In Ireland I’ve often heard people elide(?) dad to just da’. I’ve also heard “mam” instead of “mum” in some parts of Ireland, but this could just be the local accent. But ‘me’ for ‘my’ seems common all over Ireland in informal speech. The use of ‘great’ there by some people sounds strange to Americans. I’ve heard Irish speakers say “I’m very great with him” to mean they’re good friends.
Some Irish speakers also use the present progressive where Americans and Brits would just use the present: “I’m liking this” as opposed to “I like this.” Americans also use “just” a lot: “It’s not just…”, “It’s just about…”, etc.
I’ve also noticed that women in Ireland and Australia tend to pitch their voices higher in formal circumstances than a British or American woman would do.
I think, to us in Britain, “bloody” seems less strong than “bugger”, which, in turn, seems less strong/rude than “fucking”
And - heheheh - it looks as though Celyns, at least, are too fond of commas!
Whilst ducking for cover: Actually whinge is a term mostly applied to the British here…of course I would never use it like that 
Hey, a Tassie on board! I got family out that ways, in Tinderbox, just outside Hobart…
Anyhow, there’s a coupld words that get me. For some reason, when I hear someone use “heaps of” to describe a great quantity of something, it’s normally an Aussie. Also, “prolly” originally seemed to be used by Australians, although now it seems to have spread into the greater English lexicon.
As an American, I cannot tell American from Canadian (except on hearing, and then I sometimes get Wisconsonians and Minnesotans confused with our northern neighbors.) But UK or Aussie from US is easy, even from text. There are obvious giveaways, such as have been mentioned, or slightly more sublte ones like, “I’m going to university” or “He’s in hospital” which indicate a non-North American origin. Also, using the plural with collective nouns is a British English trait (i.e. “The team are doing well.”) Also, though not as reliable, is periods placed outside the quotation marks (aka “inverted commas”).
Thing is, though, Americans living in Europe tend to adopt certain British words, so one is never able to tell with an absolutely confident degree of accuracy one’s country of origin.
Ah. I rather suspected as much, but without a smilie, I couldn’t be sure. You might consider employing a winkie next time, you great pillock. (Bloody useful little bugger, innit?)
I know exactly what you’re talking aboot.
I believe you, but if I saw someone write it online, I wouldn’t go, “Oh! An Irishperson!”
I thought of something, though, ooh ooh!
I’m not sure where the line on this divides, but I bet you all can help me figure it out. I’m not certain what the grammatical term would be, but let me give an example.
UK: “Sri Lanka have defeated India in cricket.”
US: “San Francisco has defeated LA in baseball.”
There is a real difference in usage of is v. are and have v. has.
“wouldn’t” is very Irish, too. As in:
I wouldn’t be a big fan of theirs. (not “I’m not …”)
You wouldn’t have room in your car, would you? (not “Would you …” or “Do you …”)
You wouldn’t give me a hand with this? (not “Could you …”)