- (sciences) emittance, extinction coefficient. (Can we add an example for this sense?)
- (mathematics) A small number, usually in company of δ.
- For each ε > 0, there exists a δ > 0, ...
- (mathematics, computer science) empty string
- Lower case epsilon, the fifth letter of the ancient and modern Greek alphabets. Its name was εἶ, later ἒ ψιλόν, and presently έψιλον. It represents roughly the same sound in both alphabets: in Modern Greek, a somewhat lowered variant of the mid front unrounded vowel: /e/ or /e̞/. It is preceded by δ and followed by ϝ.
- (Greek-script letters) Α α (A a), Β β (B b), Γ γ (G g), Δ δ (D d), Ε ε (E e), Ζ ζ (Z z), Η η (Ē ē), Θ θ (Th th), Ι ι ℩ (I i ℩), Κ κ (K k), Λ λ (L l), Μ μ (M m), Ν ν (N n), Ξ ξ (X x), Ο ο (O o), Π π (P p), Ρ ρ (R r), Σ σ ς (S s s), Τ τ (T t), Υ υ (U u), Φ φ (Ph ph), Χ χ (Kh kh), Ψ ψ (Ps ps), Ω ω (Ō ō)
- (punctuation) · ;
- (diacritics) ᾿ ῾ ´ ` ῀ ¨ ¯ ˘