真(zhen)(zhen)空(kong)(kong)(kong)，這(zhe)一術語譯自拉丁文vacuo，其意義是(shi)虛(xu)無。其實(shi)真(zhen)(zhen)空(kong)(kong)(kong)應理解為(wei)氣(qi)體較稀薄的空(kong)(kong)(kong)間(jian)。在指定的空(kong)(kong)(kong)間(jian)內(nei)，低于一個大(da)氣(qi)壓(ya)(ya)力的氣(qi)體狀(zhuang)態(tai)統稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)態(tai)下氣(qi)體稀薄程度稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)(ya)力值表示。因此真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝實(shi)際上不(bu)是(shi)完全真(zhen)(zhen)空(kong)(kong)(kong)的，采用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝技術包(bao)裝的食(shi)品容器內(nei)的真(zhen)(zhen)空(kong)(kong)(kong)度通常在600-1333Pa。所以，又(you)將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝稱(cheng)為(wei)減壓(ya)(ya)包(bao)裝或排氣(qi)包(bao)裝。