digamma，英语单词，主要用作名词，作名词时译为“早期希腊语的第六个字母，古希腊字母的F”。

柯林斯英汉双解大词典

digamma /daɪˈɡæmə/

1.N a letter of the Greek alphabet (Ϝ) that became obsolete before the classical period of the language. It represented a semivowel like English W and was used as a numeral in later stages of written Greek, and passed into the Roman alphabet as F 古希腊字母 (Ϝ)

digamma function 双函数 ; 双伽玛函数

w digamma 蠝

digamma-function 双Γ函数

q-digamma function q双r函数

q digamma function q双γ函数

Euler digamma function 莫比乌斯函数

Gauss's digamma theorem 双伽玛函数