真(zhen)(zhen)空(kong)(kong)(kong)(kong)，這(zhe)一術(shu)語譯自拉丁文(wen)vacuo，其(qi)(qi)意義是虛(xu)無。其(qi)(qi)實真(zhen)(zhen)空(kong)(kong)(kong)(kong)應理解為(wei)氣(qi)(qi)體較(jiao)稀薄的空(kong)(kong)(kong)(kong)間。在指(zhi)定的空(kong)(kong)(kong)(kong)間內，低于一個大(da)氣(qi)(qi)壓(ya)力(li)的氣(qi)(qi)體狀(zhuang)態統稱為(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)(kong)狀(zhuang)態下氣(qi)(qi)體稀薄程度稱為(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)力(li)值(zhi)表示。因此真(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)實際上不(bu)是完(wan)全(quan)真(zhen)(zhen)空(kong)(kong)(kong)(kong)的，采用真(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)技術(shu)包裝(zhuang)的食品容(rong)器內的真(zhen)(zhen)空(kong)(kong)(kong)(kong)度通常在600-1333Pa。所以(yi)，又將(jiang)真(zhen)(zhen)空(kong)(kong)(kong)(kong)包裝(zhuang)稱為(wei)減壓(ya)包裝(zhuang)或排氣(qi)(qi)包裝(zhuang)。