真(zhen)空(kong)(kong)(kong)，這一術(shu)語譯(yi)自拉丁文vacuo，其意義是(shi)虛(xu)無。其實真(zhen)空(kong)(kong)(kong)應理解為(wei)氣(qi)體較稀(xi)薄(bo)的(de)空(kong)(kong)(kong)間。在指定的(de)空(kong)(kong)(kong)間內(nei)，低于(yu)一個大氣(qi)壓(ya)力(li)的(de)氣(qi)體狀態統(tong)稱(cheng)為(wei)真(zhen)空(kong)(kong)(kong)。真(zhen)空(kong)(kong)(kong)狀態下氣(qi)體稀(xi)薄(bo)程度稱(cheng)為(wei)真(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通(tong)常用壓(ya)力(li)值表(biao)示。因(yin)此真(zhen)空(kong)(kong)(kong)包裝(zhuang)(zhuang)實際上不(bu)是(shi)完(wan)全(quan)真(zhen)空(kong)(kong)(kong)的(de)，采用真(zhen)空(kong)(kong)(kong)包裝(zhuang)(zhuang)技術(shu)包裝(zhuang)(zhuang)的(de)食品(pin)容器(qi)內(nei)的(de)真(zhen)空(kong)(kong)(kong)度通(tong)常在600-1333Pa。所以，又(you)將(jiang)真(zhen)空(kong)(kong)(kong)包裝(zhuang)(zhuang)稱(cheng)為(wei)減壓(ya)包裝(zhuang)(zhuang)或排氣(qi)包裝(zhuang)(zhuang)。