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

• dihedrons
• dihybrid
• dihybrids
• dihydric
• dijudicate
• dijudicated
• dijudicates
• dijudicating
• dijudication
• dijudications
• dika
• dika-bread
• dika-butter
• dika-butters
• dika-oil
• dikas
• dikast
• dikasts
• dik-dik
• dike
• diked
• diker
• dikes
• dikey
• diking