Nica or NICA may refer to:

• Nīca, a village in Latvia
• NICA, pronounced "n-eye-ka" stands for the "National Interscholastic Cycling Association" and is a collection of state leagues in the USA and selected regions abroad for competitive mountain bike competitions. State NICA leagues follow NICA rules with some variation and hold races by state regions with a final championship. NICA is holding three national regional races in 2026.
• Nica, the name in some languages of Nice, a French city
• "Nica", a jazz tune composed by Sonny Clark

• Nica is an adjective which may refer to:
• Nica (name)
  • Nicaragua
  • Nicaraguan people
• National Iranian Canadian Assembly
• Nica Airlines, an alternate name for Nicaragüense de Aviación, a Nicaraguan airline
• National Institute of Circus Arts, an Australian circus school
• National Intelligence Coordinating Agency, a government agency in the Philippines
• Nica (butterfly), a genus of nymphalid butterflies in the Biblidinae subfamily
• National Ice Carving Association, a U.S. ice sculpture association
• Netherlands Indies Civil Administration, the World War II-era Dutch colonial administration in Indonesia
• Nicotine Anonymous (NicA), a stop-smoking program
• Northern Ireland Court of Appeal, part of the Courts of Northern Ireland
• Nuclotron-based Ion Collider fAcility, a proton and heavy ion collider under construction at JINR in Dubna, Russia

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