Neiden may refer to:

• Neiden, Norway, a village in Sør-Varanger, Finnmark county, Norway
• Neiden Chapel, a chapel in the village of Neiden, Sør-Varanger, Finnmark county, Norway
• Neidenelva, the Norwegian name of the Näätämö River that flows through Norway and Finland
• Neiden, Germany, a village in the municipality Elsnig, Saxony, Germany

• Cosmoclostis schouteni
• Cosmo Cosmolino
• Cosmodicy
• Cosmodiscus
• Cosmo (dog)
• Cosmodrome Baikonur
• Cosmofer
• Cosmo Films
• Cosmo Films Ltd
• Cosmo for Latinas
• Cosmo Francesco Ruppi
• Cosmo Gang: The Puzzle
• Cosmo (given name)
• Cosmogony (song)
• Cosmo Gordon Lang, 1st Baron Lang of Lambeth
• Cosmo Grant Niven Edwards
• Cosmographia Blaviana
• Cosmographia Claudii Ptolomaei Alexandrini
• Cosmo Haskard
• Cosmoid
• Cosmoid scale
• Cosmoid scales
• Cosmo Jones, Crime Smasher
• Cosmo Jones in 'Crime Smasher'
• Cosmoledo atoll