on board adjective 3exclamation 1preposition 1 adjective3 •Joining in or participating.Is that new teammate properly on board yet? •Agreeing or supporting.It's a good idea, but let's see if we can get a few more of the management team on board.Without management on board, the project has little chance of success. •Into itself or oneself.Soccer players certainly tend not to take fluids on board. — 1991 exclamation1 •The stereotypical cry of pirates when boarding a ship for close quarters combat. preposition1 •On or in (a means of transportation).On board his boat were various firearms but not much food.Even when I am on board the plane, I can never feel secure that my luggage is, too.
