luff

nouns

(nautical) the forward edge of a fore-and-aft sail that is next to the mast
is a part of
any sail not set on a yard and whose normal position is in a fore-and-aft direction
domain category
the work of a sailor
is a type of (narrower)
the outside limit of an object or area or surface; a place farthest away from the center of something
"the edge of the leaf is wavy"; "she sat on the edge of the bed"; "the water's edge"
the act of sailing close to the wind
is a type of (narrower)
riding in a sailboat

verbs

sail close to the wind
flap when the wind is blowing equally on both sides
"the sails luffed"
is a type of (narrower)
move in a wavy pattern or with a rising and falling motion
"The curtains undulated"; "the waves rolled towards the beach"