真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)，這一術(shu)語譯自拉丁(ding)文vacuo，其意義(yi)是虛無。其實(shi)(shi)真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)應理解為氣(qi)體(ti)較稀薄的(de)(de)空(kong)(kong)(kong)(kong)間(jian)。在指(zhi)定(ding)的(de)(de)空(kong)(kong)(kong)(kong)間(jian)內，低(di)于一個大氣(qi)壓力的(de)(de)氣(qi)體(ti)狀態(tai)統稱(cheng)為真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)。真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)狀態(tai)下氣(qi)體(ti)稀薄程(cheng)度稱(cheng)為真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)度（degreeofvacuum），通常用(yong)壓力值(zhi)表示。因此(ci)真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝實(shi)(shi)際上不是完(wan)全(quan)真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)的(de)(de)，采用(yong)真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝技術(shu)包裝的(de)(de)食品(pin)容器內的(de)(de)真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)度通常在600-1333Pa。所以(yi)，又(you)將真(zhen)(zhen)(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝稱(cheng)為減壓包裝或排氣(qi)包裝。