occasional

/əˈkeɪʒənəl/
adjective
  1. Happening sometimes but not regularly or often.
    • We enjoy an occasional trip to the beach.
    • The occasional thunderstorm is common in this region.
    • She makes occasional mistakes when typing quickly.
  2. Created or used for a particular event or purpose.
    • She wore an occasional dress to the formal dinner.
    • He wrote an occasional poem for the wedding.
    • The theater group performed an occasional play for the festival.