The term 'brilliantly clever' can be described by the crossword solutions of SCINTILLATING (13 letters), INGENIOUS (9 letters), MACAW (5 letters), aglare (6 letters), and MACAWS (6 letters). SCINTILLATING is an adjective that means to be dazzlingly bright or impressive. INGENIOUS is an adjective that means to be very clever, original, and inventive. MACAW is a type of large parrot with long tails and colorful feathers. Aglare is an adjective that means to be brightly lit or illuminated. Finally, MACAWS is the plural form of the word MACAW.