"aboard" in the adverb sense
1. aboard, on board
on a ship, train, plane or other vehicle
on first or second or third base
"Their second homer with Bob Allison aboard"
3. aboard, alongside
side by side
"anchored close aboard another ship"
part of a group
"Bill's been aboard for three years now"
Source: WordNet® (An amazing lexical database of English)
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