A small bright purple and yellow basslet (fish), Gramma loreto (family Grammatidae), found in the tropical West Atlantic and Caribbean, and popular in tropical marine aquaria; also called fairy basslet.
Origin
1950s. From royal + scientific Latin Gramma, genus name.
Definition of royal gramma in US English:
royal gramma
noun
A small bright purple and yellow basslet (fish), Gramma loreto (family Grammatidae), found in the tropical West Atlantic and Caribbean, and popular in tropical marine aquaria; also called fairy basslet.
Origin
1950s. From royal + scientific Latin Gramma, genus name.