真(zhen)(zhen)空(kong)(kong)(kong)(kong)，這一術(shu)語譯自拉丁文vacuo，其(qi)意義是(shi)虛無。其(qi)實(shi)真(zhen)(zhen)空(kong)(kong)(kong)(kong)應理(li)解為(wei)(wei)(wei)氣(qi)(qi)體較稀(xi)薄(bo)的空(kong)(kong)(kong)(kong)間(jian)。在指(zhi)定的空(kong)(kong)(kong)(kong)間(jian)內，低(di)于一個大(da)氣(qi)(qi)壓力的氣(qi)(qi)體狀態統稱為(wei)(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)(kong)狀態下氣(qi)(qi)體稀(xi)薄(bo)程度(du)稱為(wei)(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常用(yong)壓力值(zhi)表示。因此真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)際上(shang)不(bu)是(shi)完全(quan)真(zhen)(zhen)空(kong)(kong)(kong)(kong)的，采用(yong)真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)技(ji)術(shu)包(bao)裝(zhuang)的食品容器內的真(zhen)(zhen)空(kong)(kong)(kong)(kong)度(du)通(tong)常在600-1333Pa。所以，又將真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)稱為(wei)(wei)(wei)減(jian)壓包(bao)裝(zhuang)或排氣(qi)(qi)包(bao)裝(zhuang)。