## EnglishEdit

### EtymologyEdit

*tetra-* + *(itera)tion*; coined by Reuben Goodstein

### NounEdit

**tetration** (*uncountable*)

- (arithmetic) The arithmetic operator consisting of repeated exponentiation, by analogy with exponentiation being repeated multiplication and multiplication being repeated addition,
^{b}*a*denoting*a*to the power of*a*to the power of ... to the power of*a*, in which*a*appears*b*times. Notation:^{b}*a*, or