Equivalent word for 'overseas' for a non-island country?

Consider abroad:

in or to a foreign country

Examples:

I'm going abroad for holiday.

Investors abroad brought $1bn into the country last year.

Instead of buying clothes produced abroad, consider supporting local producers.

Source: Merriam-Webster

The U.S. is not an island but we routinely refer to foreign countries as "overseas". People quibble about whether Canada and Mexico are "overseas" as you don't have to go over any seas to get there.

In general, "abroad" and "foreign" refer to other countries regardless of any intervening water. I think "abroad" is relatively rarely used these days. We often simply say "another country". If you're talking about something brought to this country from another country, we say "imported".

Common ways to express your examples:

I'm going to another country for a vacation.

I'm going abroad for a vacation.

Foreign investors brought $1bn into the country last year.

Instead of buying imported clothes, consider supporting local producers.

Instead of buying clothes produced in other countries, ...

I'm suddenly reminded of a news program where the anchorman introduced a reporter's special report by saying, "And now Sally Jones (or whatever her name was) will tell us what she learned when she was a broad ... I mean overseas."

I think 'overseas' was originally a British term, for the obvious reason that visiting any place 'abroad' involved going 'overseas'. It was widely used up to the 1960s - remember BOAC (British Overseas Airways Corporation).

My own experience whilst living in Australia was that they and the New Zealanders had retained it, perhaps since they were each far more isolated from elsewhere by sea than the 'mother country' was.

It was a societal landmark for middle-aged people to say that their children 'were overseas', meaning they were taking an extended working holiday in Europe or America. It seemed to have that connotation more than it simply meaning they had gone on holiday.

As for Europeans, they would be unlikely to use the word 'overseas'. If they were speaking in their own language, if at all, they might say 'Nous allons à l’étranger cette année' - 'We are going abroad (to foreign lands) this year'. But French people nowadays don't always regard going to Germany as going abroad, as it doesn't involve any passport check, or even that you slow down on the motorway as you pass a sign which says 'Deutschland'.

'International' is another option. (http://en.wiktionary.org/wiki/international#Adjective - sense #5)

From or between other countries [ref]

e.g.

I'm travelling internationally tomorrow, so I'll need some foreign currency.

International investors brought $1bn into the country last year.

Instead of buying clothes produced internationally, consider supporting local producers.