Having a high neckline: a high-necked sweater. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "high-necked" in a sentence
"Reuters Vera Wang and Peter Som pictured showed long dresses that were high-necked but slinky."
"Later when Mavis is invited to a baby's naming ceremony, she takes on another guise: that of a sober career woman with her hair in a bun, wearing a high-necked dress and conservative spectator pumps."
"She was pictured in a bathrobe, a business suit, and finally -- as the sexy chick -- in a high-necked evening gown that exposed nothing but her arms."