at first it's sticking out (bulges out), then concave (bulges out).
It was a typo, I meant bulges in.
buldge
to stick out from something in a round shape
• South of Benghazi the coastline bulges out then in.
OALD
That means that the line of the coast is sinuous -- at first it's sticking out (bulges out), then concave (bulges out). Is this right?
Thanks.