epsilon
Concise Oxford English Dictionary © 2008 Oxford University Press:
epsilon /ˈɛpsɪlɒn, ɛpˈsʌɪlɒn/
▶noun the fifth letter of the Greek alphabet (Ε, ε), transliterated as ‘e’.
■ [as modifier] denoting the fifth in a series of items or categories.
– origin Gk, ‘bare or simple E’, from psilos ‘bare’.
'epsilon' also found in these Oxford entries:
