Upsilon — υ Greek Letter Symbol
υ
Upsilon — υ / Υ
20th letter of the Greek alphabet · pronounced /ˈʌpsɪlɒn/
PhysicsMathematicsParticle Physics
Copy symbol
υ
Lowercase upsilon
Υ
Uppercase Upsilon
Technical reference
| Unicode (lowercase) | U+03C5 |
| Unicode (uppercase) | U+03A5 |
| HTML entity | υ |
| HTML decimal | υ |
| LaTeX | \upsilon |
| Python / Unicode escape | \u03c5 |
| Alt code (Windows) | Alt + 965 |
Uses in science & engineering
Upsilon meson (particle physics)
Heavy meson composed of a bottom quark and its antiquark. Discovered in 1977.
\(\Upsilon(1S), \Upsilon(2S), \Upsilon(3S)\)
Frequency (alternative)
Used in some older texts as an alternative symbol for frequency.
\(\upsilon = \frac{c}{\lambda}\)
Kinematic viscosity (alternative)
Occasionally used instead of ν for kinematic viscosity in some European texts.
\(\upsilon = \frac{\mu}{\rho}\)
Related symbols
How to insert in applications
Windows
Best option: copy from this page.
Or press Win + . to open emoji & symbols panel.
Alt codes work only in Word/Notepad with NumLock on and English layout — not in browsers.
Or press Win + . to open emoji & symbols panel.
Alt codes work only in Word/Notepad with NumLock on and English layout — not in browsers.
macOS
Press ⌃⌘Space → Character Viewer → search “upsilon”
Microsoft Word
Type 03c5 then press Alt+X
Google Docs
Insert → Special characters → search by name
Excel
Insert → Symbol → Subset: Greek → select symbol
LaTeX
Use in math mode: $ … $
Python
Use Unicode escape or chr()
HTML / CSS
Use HTML entity or decimal code