Citrus medica and Citrus tree

Citrus medica noun - Thorny evergreen small tree or shrub of India widely cultivated for its large lemonlike fruits that have thick warty rind.

Citrus tree and citrus medica are semantically related. In some cases you can use "Citrus tree" instead a noun phrase "Citrus medica".

Citrus tree noun - Any of numerous tropical usually thorny evergreen trees of the genus Citrus having leathery evergreen leaves and widely cultivated for their juicy edible fruits having leathery aromatic rinds.

Citrus medica and citrus tree are semantically related. Sometimes you can replace phrase "Citrus medica" with "Citrus tree", this phrases are similar.