The noun camaraderie means a feeling of loyalty, trust and good-fellowship among friends (usually knowing each other for a long time and sharing memories and experiences together).  

Synonyms are companionship, intimacy, togetherness or comradeship.

The word origins from Middle French (1840) camaraderie from camarade meaning “roommate, companion or group sleeping in one room”. It also derived from Old Spanish camera or camara meaning “chamber”.

 The camaraderie among the group is unique.

This club was missing the camaraderie a club usually develops over time.

I miss the camaraderie of the people you would meet in an adventure trip through Africa.