The plumage of an adult lilac-crowned amazon is primarily green with yellowish underparts and black edging. The forehead is a maroon color with a light blue-lilac neck, nape, and crown. The cheeks and ear coverts are a greenish yellow that lacks the edging that is present in most of the plumage. The primary feathers are dark blue with the secondary feathers being green while being tipped with the same dark blue coloring. Furthermore, the initial five secondary feathers have a bright red speculum on the edge of the feathers.