Aboard means on or onto a ship, plane, train or other vehicle — all aboard, welcome aboard. Abroad means in or to a foreign country — working abroad, a year abroad. The letters are nearly the same; the meanings have nothing in common.
The core difference
- aboard — on or into a vessel or vehicle. The passengers went aboard, there were 200 people aboard, welcome aboard the team.
- abroad — in or to another country. She studied abroad, goods from abroad, holidays abroad.
The tell
Split the words. A-board is the board — the deck — of a ship; a-broad is "out over a broad area". Aboard needs something to be on; abroad needs a border to be beyond. Two letters swap places between them, which is why the slip is a typing error as often as a thinking one.
In use
- aboard — Once aboard, find your seat. All 180 passengers aboard were safe.
- abroad — He spent a year abroad. Demand from abroad is rising.
Common slips
- all abroad! → all aboard!
- she moved aboard for work → she moved abroad for work
A board is a deck; broad is wide open country.
Aboard, on board, onboard
Aboard and on board mean the same thing and are interchangeable: welcome aboard, welcome on board. Onboard as one word is an adjective — the onboard computer — and, in business jargon, a verb for inducting a new starter. None of the three has anything to do with abroad.
Where the words come from
Aboard is on + board, the side or deck of a ship, from the fifteenth century. Abroad is on + broad and originally meant "widely, out and about" — there is a rumour abroad — before narrowing to "overseas" around the same period.
Frequently asked questions
Is it "all aboard" or "all abroad"?
All aboard. It is the call to board a train or ship.
Does abroad always mean overseas?
Almost always now. The older sense of "out and about, at large" survives in phrases like "there is a rumour abroad" and in some fiction.
Can you say "welcome aboard" to a new colleague?
Yes. It is a common figurative use — the team is the ship.