真(zhen)空(kong)(kong)(kong)(kong)，這(zhe)一術(shu)語譯自拉(la)丁文vacuo，其(qi)意(yi)義是虛無。其(qi)實真(zhen)空(kong)(kong)(kong)(kong)應理解為(wei)氣(qi)體較稀薄的(de)(de)空(kong)(kong)(kong)(kong)間。在指定的(de)(de)空(kong)(kong)(kong)(kong)間內，低于一個大氣(qi)壓(ya)力的(de)(de)氣(qi)體狀態(tai)統稱(cheng)為(wei)真(zhen)空(kong)(kong)(kong)(kong)。真(zhen)空(kong)(kong)(kong)(kong)狀態(tai)下氣(qi)體稀薄程度(du)稱(cheng)為(wei)真(zhen)空(kong)(kong)(kong)(kong)度(du)（degreeofvacuum），通常用壓(ya)力值表示。因此(ci)真(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)(zhuang)實際上不是完(wan)全真(zhen)空(kong)(kong)(kong)(kong)的(de)(de)，采用真(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)(zhuang)技術(shu)包裝(zhuang)(zhuang)的(de)(de)食品容(rong)器(qi)內的(de)(de)真(zhen)空(kong)(kong)(kong)(kong)度(du)通常在600-1333Pa。所以，又將真(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)(zhuang)稱(cheng)為(wei)減壓(ya)包裝(zhuang)(zhuang)或(huo)排(pai)氣(qi)包裝(zhuang)(zhuang)。