真(zhen)(zhen)(zhen)空(kong)(kong)(kong)，這一術語(yu)譯自拉丁文vacuo，其意義是虛無。其實(shi)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)應理解為氣(qi)體(ti)較稀薄的(de)空(kong)(kong)(kong)間(jian)。在指定的(de)空(kong)(kong)(kong)間(jian)內，低于一個大氣(qi)壓(ya)力的(de)氣(qi)體(ti)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(ti)稀薄程度(du)(du)稱為真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)(du)（degreeofvacuum），通常用壓(ya)力值表示。因此真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)際上(shang)不(bu)是完(wan)全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)的(de)，采用真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)技術包(bao)裝(zhuang)的(de)食(shi)品(pin)容(rong)器內的(de)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)(du)通常在600-1333Pa。所以，又將(jiang)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)。