七なな三さん一いち部ぶ隊たいMeaningsNoun1. Unit 731 (biological warfare unit of the Japanese Imperial Army) (Historical)Other spellings７なな３さん１いち部ぶ隊たい0%Kanji used七seven三three一one部section隊squadComposed of七ななsevenNumeric三さんthree; 3Numeric一いちone; 1; best; first; foremost; beginning; start; a (single); one (of many); ace; …Numeric部ぶ隊たいforce; unit; corps; squad; troops; partyNoun