From Longman Dictionary of Contemporary Englishaquamarineaq‧ua‧ma‧rine /ˌækwəməˈriːn◂ $ ˌæ-, ˌɑː-/ noun 1 
[countable, uncountable]DCJ a greenish blue jewel, or the type of stone it comes from2 [uncountable]CC a greenish blue colour —aquamarine adjective
[countable, uncountable]DCJ a greenish blue jewel, or the type of stone it comes from2 [uncountable]CC a greenish blue colour —aquamarine adjectiveExamples from the Corpus
aquamarine• Deep rose merged with the turquoise and aquamarine of fast-fading night.• The television screen became a rectangle of icy aquamarine.• Luckily it had short sleeves, and she knew that the subtle shade of pale aquamarine suited her colouring.Origin aquamarine (1500-1600) Latin aqua marina “sea water” 