Saint Peter's wreath and Spirea

Saint Peter's wreath noun - Shrub having copious small white flowers in spring.

Spirea and Saint Peter's wreath are semantically related. In some cases you can use "Spirea" instead a noun phrase "Saint Peter's wreath".

Spirea noun - A Japanese shrub that resembles members of the genus Spiraea; widely cultivated in many varieties for its dense panicles of flowers in many colors; often forced by florists for Easter blooming.

Saint Peter's wreath and spirea are semantically related. Sometimes you can replace phrase "Saint Peter's wreath" with "Spirea", this terms are similar.