sunbath

/ˈsʌnˌbæθ/
noun
  1. An act of sitting or lying in the sun to expose the skin to sunlight, typically to get a tan or for relaxation.
    • She took a long sunbath on the beach to work on her tan.
    • The doctor recommended a short sunbath each day for vitamin D.
    • After a quick sunbath, he went for a swim in the ocean.