Embarkation is the act of getting onto a ship or a plane, or of putting people or goods onto one. It is the noun for that moment at the start of a trip — the going aboard, not the journey itself. You meet it on signs and in formal travel language: embarkation time, point of embarkation. Ordinary chat usually skips it and says “boarding.” It feels official, the kind of word a port, an airline, or the army would print. It names the action or the time of going on, not the ship and not the person.

登船、登機（指動作或時間）