1. Carefree and happy and lighthearted
   "a merry blithesome nature"
   - blithe, lighthearted, lightsome, light-hearted

See also: cheerful

• orthogonal
• orthogonal opposition
• orthogonality
• orthogonally
• orthographic
• orthographical
• orthographically
• orthography
• orthology
• orthomolecular
• orthomorphic projection
• orthomyxovirus
• orthonormal
• orthopaedic
• orthopaedics
• orthopaedist
• orthopedic
• orthopedical
• orthopedics
• orthopedist
• orthophosphate
• orthophosphoric acid
• orthophosphorous acid
• orthopnea
• orthopraxy