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

• snowmobiling
• snow-on-the-mountain
• snow-on-the-mountains
• snowpack
• snowpacks
• snow pea
• snow peas
• snow plant
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• snowplough
• snowploughed
• snowploughing
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• snows
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• snowshoe
• snowshoed
• snowshoe hare
• snowshoe hares
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• snowshoe rabbit
• snowshoe rabbits
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• snowslip