Reverse Polish notation
WordNet
noun
(1) A parenthesis-free notation for forming mathematical expressions in which each operator follows its operands
WiktionaryText
Noun
- an arithmetic notation in which numbers precede the operators to be applied to them.
- Back in my day, we had reverse Polish notation calculators: You had to write "2 4 3 * +" instead of "2 + 4 * 3".