Not elaborate, showy, or intensive; modest, restrained, or subdued. The wedding was a low-key affair, with only close family and friends in attendance.
Relaxed and easy-going; not tense or stressful. We decided to have a low-key weekend at home, just watching movies and relaxing.
(Photography, art) Dominated by dark tones and minimal highlights. The portrait was shot in a dramatic low-key style with deep shadows.