epsilon

noun6

1. •
   The fifth letter of the Greek alphabet, ε or Ε, preceded by delta (Δ, δ) and followed by zeta (Ζ, ζ).
2. •
   An arbitrarily small quantity.
3. •
   (informal) Something negligible or insignificant.

   • Yes, we have to convert all the symbol names to upper case at startup, but that’s epsilon.
4. •
   In IPA, the phonetic symbol ɛ that represents the open-mid front unrounded vowel.
5. •
   The percentage change in an option value with respect to the underlying dividend yield.
6. •
   (informal) A small child.