真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)，這一術語譯自拉丁(ding)文vacuo，其意義是(shi)(shi)虛(xu)無。其實真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)應理解(jie)為氣(qi)體(ti)較稀(xi)薄的(de)空(kong)(kong)(kong)(kong)間。在指(zhi)定(ding)的(de)空(kong)(kong)(kong)(kong)間內，低于一個大氣(qi)壓(ya)力的(de)氣(qi)體(ti)狀(zhuang)態統稱(cheng)為真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)。真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)狀(zhuang)態下氣(qi)體(ti)稀(xi)薄程度稱(cheng)為真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)度（degreeofvacuum），通常用(yong)壓(ya)力值表(biao)示(shi)。因此真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)實際上不是(shi)(shi)完(wan)全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)的(de)，采用(yong)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)技術包(bao)裝(zhuang)(zhuang)的(de)食品容器內的(de)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)度通常在600-1333Pa。所(suo)以(yi)，又將真(zhen)(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)稱(cheng)為減壓(ya)包(bao)裝(zhuang)(zhuang)或排氣(qi)包(bao)裝(zhuang)(zhuang)。