真(zhen)(zhen)空(kong)(kong)(kong)，這一(yi)術語譯自拉(la)丁文vacuo，其(qi)意義(yi)是(shi)虛無。其(qi)實(shi)真(zhen)(zhen)空(kong)(kong)(kong)應理解為(wei)氣(qi)(qi)體(ti)較(jiao)稀(xi)薄的(de)空(kong)(kong)(kong)間。在指(zhi)定的(de)空(kong)(kong)(kong)間內(nei)，低于一(yi)個大氣(qi)(qi)壓力(li)的(de)氣(qi)(qi)體(ti)狀(zhuang)(zhuang)態統稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)(zhuang)態下氣(qi)(qi)體(ti)稀(xi)薄程度(du)稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通常(chang)用壓力(li)值表(biao)示。因此(ci)真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)際上不是(shi)完(wan)全真(zhen)(zhen)空(kong)(kong)(kong)的(de)，采(cai)用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)技(ji)術包(bao)裝(zhuang)的(de)食品容器內(nei)的(de)真(zhen)(zhen)空(kong)(kong)(kong)度(du)通常(chang)在600-1333Pa。所以，又將(jiang)真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)稱(cheng)為(wei)減壓包(bao)裝(zhuang)或排氣(qi)(qi)包(bao)裝(zhuang)。