Meaning : On a ship, train, plane or other vehicle.
Synonyms : on board
Meaning : On first or second or third base.
Example :
Their second homer with Bob Allison aboard.
Meaning : Part of a group.
Example :
Bill's been aboard for three years now.
Aboard ka meaning, vilom shabd, paryayvachi aur samanarthi shabd in Hindi. Aboard ka matlab kya hota hai?