Greenish-blue colour (4)
(Other definitions for aqua that I've seen before include "Blue tinged with green" , "Water (L)" , "(Denoting) water (Lat)" , "Latin for water" , "- - Libra" .)
(Other definitions for teal that I've seen before include "bird" , "Duck - dark greenish-blue" , "Small, short-necked duck" , "Bluish shade of green" , "Dark greenish-blue colour" .)