On-board things are the things a ship, plane, train, or car already carries with it. An on-board computer, on-board cameras, on-board meals, on-board toilets: they belong to the vehicle, not something you bring from outside. You will also see onboard as one word; the meaning does not change.

On-board things are指的是 a ship, plane, train, or car船、飛機、火車或汽車 already carries with it本來就隨車帶著的 the things那些東西。An on-board computer車載電腦、on-board cameras機上鏡頭、on-board meals機上餐點、on-board toilets車上廁所：they belong to the vehicle它們屬於交通工具本身，not something you bring from outside不是你從外面帶上來的東西。You will also see你也會看到 onboard as one word連在一起寫成 onboard；the meaning does not change意思不變。

Manuals and ads like this word; in speech people often just say 'on the plane' or 'on the ship'.

Manuals and ads說明書和廣告 like this word喜歡這個字；in speech口語裡 people often just say人們常常只說 'on the plane' 或 'on the ship'。

Though actually, 'Are you on board with this plan?' is a different, looser use — that means 'Do you agree? Will you join us?' That is not this sense. This sense is about people and things physically on the vehicle.

Though actually不過其實，'Are you on board with this plan?'這個計畫你加入嗎？is a different, looser use是另一種比較鬆的用法——that means那是在問 'Do you agree?你同意嗎？Will you join us?你要加入我們嗎？' That is not this sense那不是這個義項。This sense這個義項 is about講的是 people and things人和東西 physically on the vehicle實際在交通工具上。