invex不变凸INVabbr.发明者(=Inventor)abbr.反相器(=Inverter)abbr.体外授精(=in vitro fertilization)involute push broach渐开线推刀invoicing department货品计价部inveteerate criminal[法] 惯犯, 屡教不改犯involutive quantalel对合Quantaleinvitrofertilization体外受精invariance condition不变的条件involatile substance不挥发性物质involution spur gear渐开线invigorating therapy补法, 补虚, 补养, 补益invariability moment不变矩