Physalia physalis, a marine cnidarian consisting of a floating colony of hydrozoans attached to a float, superficially resembling a jellyfish.
Used other than figuratively or idiomatically: see Portuguese, man-of-war.
Cornflower blue.
A plant of the species Cichorium intybus.
A small annual plant in the family Asteraceae, Centaurea cyanus, usually with bushy blue flowers which grows natively in European cornfields (i.e. wheatfields).
Of a blue colour, as that of the cornflower; cornflower blue.