prefix notation prefix syntax <language> (Or "prefix syntax") One of the possible orderings of {functions} and {operands}: in prefix notation the function precedes all its operands. For example, what may normally be written as "1+2" becomes "(+ 1 2)". A few languages (e.g., {lisp}) have strictly prefix syntax, many more employ prefix notation in combination with {infix notation}. Compare: {postfix notation}. (2001-02-14)