繁はん分ぶん数すうはんぶんすうMeanings1nouncomplex fractionA fraction where the numerator, denominator, or both contain fractions. Used in mathematics.繁はん分ぶん数すうを簡かん単たんな分ぶん数すうに直なおす方ほう法ほうを習ならった。We learned how to simplify a complex fraction into a simple fraction.