真(zhen)(zhen)(zhen)空(kong)(kong)(kong)，這一術(shu)語譯(yi)自拉丁文vacuo，其意義(yi)是虛無(wu)。其實真(zhen)(zhen)(zhen)空(kong)(kong)(kong)應理解為(wei)(wei)氣體(ti)較(jiao)稀(xi)薄的空(kong)(kong)(kong)間。在指定(ding)的空(kong)(kong)(kong)間內，低于(yu)一個大氣壓(ya)(ya)力(li)的氣體(ti)狀態(tai)統(tong)稱為(wei)(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)(zhen)空(kong)(kong)(kong)狀態(tai)下氣體(ti)稀(xi)薄程度(du)稱為(wei)(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常用壓(ya)(ya)力(li)值表示(shi)。因此真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)實際上(shang)不是完全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)的，采用真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)技術(shu)包(bao)(bao)裝(zhuang)的食品(pin)容(rong)器內的真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)通(tong)常在600-1333Pa。所以，又將真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)稱為(wei)(wei)減壓(ya)(ya)包(bao)(bao)裝(zhuang)或排氣包(bao)(bao)裝(zhuang)。