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

• hobby-horsical
• hobbyism
• hobbyisms
• hobbyist
• hobbyists
• hobbyless
• hobday
• hobdayed
• hobdaying
• hobdays
• hobgoblin
• hobgoblinism
• hobgoblinisms
• hobgoblinries
• hobgoblinry
• hobgoblins
• hobjob
• hobjobbed
• hobjobber
• make sense of
• make sheep's eyes at
• makeshift
• makeshifts
• make short work of
• make so free as to