Noun
(nautical) The first port that a vessel calls in at after the start of a voyage
After leaving from Southampton, our first port of call will be Gibraltar.
(idiomatic) The first place to go to start a process.
When you move to a new country, your first port of call is often the local police.
To find the meaning of a word, your first port of call should be a decent dictionary.
If I could time travel into the future, my first port of call would be the point where medical technology is at its best because, like most people on this planet, I have this aversion to dying. Neal Asher