What does aboard mean?
Aboard functions as both an adverb and a preposition relating to being on or entering a means of transport — typically a ship, aircraft, train, bus, or spacecraft. As an adverb it describes movement or position ('the crew went aboard'), while as a preposition it links a person or thing to the vehicle itself ('everyone aboard the ferry was safe'). The word carries a distinctly nautical heritage: it derives from the French phrase à bord, meaning 'on board' or literally 'to the plank-side' of a vessel, with bord ultimately tracing back to Old Norse bóth. Though its roots are maritime, modern usage extends readily to aviation and even spaceflight, giving phrases like 'welcome aboard' a familiar, almost ceremonial warmth. Aboard is standard in both British and American English and appears frequently in travel announcements, safety notices, and news reporting.
Onto or in a ship, aircraft, train, or other vehicle.
"Once everyone was safely aboard, the train pulled away."
Most commonly used with verbs of motion (go aboard, come aboard) or state (be aboard).
On or in (a ship, aircraft, train, or other vehicle).
"There were three journalists aboard the flight."
Every time you say 'welcome aboard,' you're echoing the Vikings — the word traces back to the Old Norse 'bord,' meaning a ship's plank side.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of aboard
Aboard entered English in the Middle Ages from the Old French phrase à bord, meaning 'on board (a ship),' where bord referred to a ship's plank side or edge. The French bord itself came from Germanic origins, cognate with Old Norse bóth and ultimately related to the English word 'board.' Its earliest uses were strictly nautical, but by the nineteenth century the word had extended naturally to railways, and later to aircraft and spacecraft.
How aboard is actually used
Aboard is neutral to slightly formal register; 'on board' is interchangeable in most contexts. It applies specifically to vehicles — especially ships, planes, trains, buses, and spacecraft — not buildings.
Easily confused with aboard
Abroad means in a foreign country, while aboard means on a vehicle such as a ship, plane, or train.