What does "neckline" mean?

The line formed by the edge of an article of clothing that surrounds the neck, especially as seen at the front.

What is a synonym for "neckline"?

Common synonyms include: collar line, decollete, encolure, neck edge, neck opening.

/ˈnɛkˌlaɪn/ noun

noun ·Rare ·Advanced level

Noun

1
The line formed by the edge of an article of clothing that surrounds the neck, especially as seen at the front.
2
the line formed by the edge of a garment around the neck wordnet

"The ravishing beauty queen wearing a blue velvet gown with a plunging neckline struck a pose on the red carpet."

From neck + line.