• Main (river), a major river and tributary of the Rhine in Germany
• Main River (Chukotka), a river in Far Eastern Siberia
• Main River, an unincorporated community in Weldford Parish, New Brunswick, Canada
• Main River (Newfoundland), a river in Newfoundland, Canada
• Main (Northern Ireland), a river in Northern Ireland as seen at near the town of Ballymena
• Saint Laurent Boulevard, a street in Montreal, Quebec, Canada is known as "The Main"
• Spanish Main, a name given to the Caribbean coast
• Main Street, a generic street name
• Main (lunar crater), a crater on the moon
• Main function (programming), a common function in some programming languages
• Main (surname), people with the surname Main
• Main (band), experimental musicians
• Ma'in, alternate spelling for the Minaeans, an ancient people of modern-day Yemen during the 1st millennium BC
• Water main
• Main course
• Gas main
• Chas. T. Main, an engineering company, later bought by Parsons Corporation
• main as a synonym for the ocean, as in the song "Sailing, Sailing"
• Mountain Area Information Network, an Internet service provider and web hosting service and operator of WPVM-LP (MAIN-FM) Asheville, North Carolina, USA

För cigarettmärket, se Main (tobak).

• Ministerstwo Edukacji Narodowej
• MEN - ang. Multiple endocrine neoplasia, genetycznie uwarunkowany zespół rozsianego nowotworu wielogruczołowego.
• Men - bóg księżyca i uzdrowicieli czczony w Anatolii.

Przepływa ona przez przez następujące większe miasta:

• Bamberg
• Würzburg
• Aschaffenburg
• Hanau
• Offenbach nad Menem
• Frankfurt nad Menem
• Wiesbaden