真(zhen)(zhen)空(kong)(kong)(kong)，這一術語譯自(zi)拉丁文vacuo，其意義是(shi)虛無。其實(shi)(shi)真(zhen)(zhen)空(kong)(kong)(kong)應理解為(wei)氣體較稀薄的(de)空(kong)(kong)(kong)間。在指(zhi)定的(de)空(kong)(kong)(kong)間內，低于一個大氣壓(ya)力(li)的(de)氣體狀態統稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀態下氣體稀薄程度稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)力(li)值表示。因此真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)(shi)際上不是(shi)完全真(zhen)(zhen)空(kong)(kong)(kong)的(de)，采用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)技術包(bao)裝(zhuang)的(de)食品容(rong)器(qi)內的(de)真(zhen)(zhen)空(kong)(kong)(kong)度通常在600-1333Pa。所以，又將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)稱(cheng)為(wei)減壓(ya)包(bao)裝(zhuang)或排氣包(bao)裝(zhuang)。