upsilon /ūp-sīˈlon, ŭp-, ūpˈsi- or upˈsi-/ or ypsilon /ip-sīˈlon or ipˈsi-/

1. The twentieth letter of the Greek alphabet (Υ, υ)
2. As a numeral υˈ = 400, ˌυ = 400000
3. A short-lived heavy subatomic particle produced when beryllium nuclei are bombarded with high-energy protons

• Mahadeva
• maharaja
• maharajah
• maharajahs
• maharajas
• maharanee
• maharanees
• maharani
• maharanis
• maharishi
• maharishis
• mahatma
• mahatmas
• Mahayana
• Mahayanist
• maha yoga
• Mahdi
• Mahdiism
• Mahdiist
• Mahdism
• Mahdist
• Mahican
• mahi-mahi
• mah-jong
• mah-jongg