1. Characterized by hard work and perseverance
   - hardworking, industrious, tireless

See also: diligent

• recrudescence
• recrudescent
• recruit
• recruiter
• recruiting-sergeant
• recruitment
• recrystallisation
• recrystallization
• rectal
• rectal artery
• rectal reflex
• rectal vein
• rectangle
• rectangular
• rectangularity
• rectifiable
• rectification
• rectified
• rectifier
• rectify
• rectifying tube
• rectifying valve
• rectilineal
• rectilinear
• rectilinear regression