A "fitted turtleneck" refers to a tight-fitting sweater or top with a high, rolled neckline that covers most of the neck and fits closely to the body. Full definition
A slightly fitted turtleneck top with only four pattern pieces? (diyraven.com)
Oatmeal colored wool is hand knit in a traditional slim fit turtleneck sweater circa 1970. (1stdibs.com)
In general I like fitted turtlenecks for this sort of application, but I do play around with what I have depending on the neckline of the dress I'm layering. (tailoredandtrue.com)