day·mark or day mark 
(dāmärk′)
(dāmärk′)n.
A distinctive pattern, color, or shape of a lighthouse or other navigational aid, used to identify it by day.
daymarkCape Hatteras Lighthouse, the tallest brick lighthouse in the United States,
Hatteras Island,
North Carolina
- submaxilla
- submaxillary
- submediant
- submerge
- submerged
- submergence
- submergibility
- submergible
- submerse
- submersed
- submersible
- submersion
- submicroscopic
- submicroscopically
- submillimeter radiation
- subminiature
- subminiaturization
- subminiaturize
- subminimum wage
- submiss
- submission
- submissive
- submissively
- submissiveness
- submit