真(zhen)(zhen)(zhen)空(kong)(kong)(kong)，這一術(shu)(shu)語譯自拉丁文vacuo，其意義是虛無。其實真(zhen)(zhen)(zhen)空(kong)(kong)(kong)應理解(jie)為(wei)氣體(ti)較稀薄的(de)(de)空(kong)(kong)(kong)間(jian)。在(zai)指定的(de)(de)空(kong)(kong)(kong)間(jian)內(nei)，低于一個大氣壓(ya)力的(de)(de)氣體(ti)狀(zhuang)態(tai)(tai)統稱為(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)態(tai)(tai)下(xia)氣體(ti)稀薄程度稱為(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)力值表示。因此真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝實際(ji)上不(bu)是完全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)的(de)(de)，采用真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝技術(shu)(shu)包(bao)裝的(de)(de)食品容(rong)器(qi)內(nei)的(de)(de)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度通常在(zai)600-1333Pa。所以，又將真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝稱為(wei)減壓(ya)包(bao)裝或排(pai)氣包(bao)裝。