真(zhen)(zhen)(zhen)空(kong)(kong)(kong)，這一術語譯自拉丁文vacuo，其意(yi)義(yi)是(shi)虛無。其實真(zhen)(zhen)(zhen)空(kong)(kong)(kong)應理解(jie)為氣(qi)體較稀(xi)薄的(de)空(kong)(kong)(kong)間(jian)。在(zai)指定的(de)空(kong)(kong)(kong)間(jian)內，低于一個大氣(qi)壓(ya)力(li)的(de)氣(qi)體狀態統稱為真(zhen)(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)(zhen)空(kong)(kong)(kong)狀態下氣(qi)體稀(xi)薄程(cheng)度(du)稱為真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通常(chang)用(yong)壓(ya)力(li)值表示。因此(ci)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)實際上不是(shi)完全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)的(de)，采(cai)用(yong)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)技術包(bao)裝(zhuang)的(de)食品容器內的(de)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)通常(chang)在(zai)600-1333Pa。所以(yi)，又將真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)稱為減壓(ya)包(bao)裝(zhuang)或排(pai)氣(qi)包(bao)裝(zhuang)。