Is it grammatically correct for a pilot or airline cabin crew to say "welcome on board", rather than "welcome aboard?" Is there a difference?


On board describes that something is aboard a vessel i.e., the location of something or someone

Onboard is one word (sometimes hyphenated—on-board) when it comes before the noun it modifies (e.g., onboard radio, onboard computer). Elsewhere, writers usually make on board two words. For instance, one might write, “We brought a radio on board so we could have an onboard radio.” Reference Onbaord vs on board

It's rather an idiomatic phrase (or a quasi-adverb)

Examples: There are no medical physicians on board. Smoking is not allowed on board.

Aboard modifies an action and is often followed by reference of the vessel, e.g. to step aboard a something.

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"aboard" is only a contraction of "on board". May be pilots prefer "on board", but actually there is no difference between the two variants.

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    No, it's not a "contraction". The a- prefix occurs in many words (abed, abreast, ashore, ajar, asleep, etc.). – FumbleFingers Sep 15 '14 at 18:12
  • Abed obviously derives from in bed. – rogermue Sep 15 '14 at 18:14
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    It quite obviously does not! The a- prefix/preposition has been validly used in English for centuries with the general sense of expressing position within, situation, etc. The fact that you can in most contexts replace it with a different preposition doesn't mean the a- form is some kind of later derivation. – FumbleFingers Sep 15 '14 at 18:25
  • @FumbleFingers I agree. Abed is a 16th-century form, certainly used by Shakespeare, most famously in Henry V - And gentlemen in England, now abed; Shall think themselves accursed they were not here. It is also still used in Norfolk, or was when I was young. My parents always said abed for 'in bed'. – WS2 Sep 15 '14 at 18:55
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    @FumbleFingers It actually does. The a- prefix is etymologically just a development of unstressed of, in, or on. I agree that they’re not contractions, but aboard does come from on board, and abed does come from in bed. The fact that the ‘full’ forms can still be used is just because both the noun and the preposition are still both part of the language and the collocation is literal and obvious enough to be remade productively. This isn’t always the case: anew comes from *of new, which is less literal and has disappeared from the language. – Janus Bahs Jacquet Sep 15 '14 at 20:52

We are on board the plane because we have boarded the aircraft.

Aboard the ship, we watched the waves.

Perhaps a bit silly, but:

As you are now on board, welcome aboard the our vessel.

As you are now aboard (the vessel) let me say welcome on board!

I don't see any grammitical difference, rather it seems to be usage as Fumble (hi ya Fumble :) says. (And there's Amid ship - center of ship.)

It would be even more silly, but grammatically correct, to say:

As you are now aboard, let me say welcome aboard.

I wonder if the word 'board' derives from the planks / boards used from dock to ship to enter the vessel?

"Arrr matey, Howard, walk the plank off board!"

protected by tchrist Mar 1 '15 at 19:09

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