真(zhen)空(kong)(kong)(kong)，這一術(shu)語譯(yi)自拉丁文vacuo，其意(yi)義是虛無。其實(shi)(shi)真(zhen)空(kong)(kong)(kong)應理解為(wei)氣(qi)(qi)體較(jiao)稀(xi)薄的空(kong)(kong)(kong)間。在指定的空(kong)(kong)(kong)間內，低(di)于一個(ge)大氣(qi)(qi)壓(ya)(ya)力(li)(li)的氣(qi)(qi)體狀態統稱為(wei)真(zhen)空(kong)(kong)(kong)。真(zhen)空(kong)(kong)(kong)狀態下氣(qi)(qi)體稀(xi)薄程度稱為(wei)真(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)(ya)力(li)(li)值(zhi)表示。因此真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)(shi)際上不是完全真(zhen)空(kong)(kong)(kong)的，采用真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)技(ji)術(shu)包(bao)裝(zhuang)的食品(pin)容器(qi)內的真(zhen)空(kong)(kong)(kong)度通常在600-1333Pa。所以，又將真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)稱為(wei)減壓(ya)(ya)包(bao)裝(zhuang)或排氣(qi)(qi)包(bao)裝(zhuang)。