Measles and Three-day measles

Measles noun - An acute and highly contagious viral disease marked by distinct red spots followed by a rash; occurs primarily in children.

Three-day measles and measles are semantically related. In some cases you can replace phrase "Three-day measles" with "Measles", this terms are similar.

Three-day measles noun - A contagious viral disease that is a milder form of measles lasting three or four days; can be damaging to a fetus during the first trimester.

Measles and three-day measles are semantically related. You can use "Measles" instead a noun phrase "Three-day measles".