真(zhen)(zhen)空(kong)(kong)(kong)(kong)，這一術語譯自拉丁(ding)文vacuo，其意義是虛無。其實(shi)真(zhen)(zhen)空(kong)(kong)(kong)(kong)應理解為(wei)(wei)氣體較稀薄的(de)(de)空(kong)(kong)(kong)(kong)間。在指定(ding)的(de)(de)空(kong)(kong)(kong)(kong)間內，低于(yu)一個大氣壓(ya)力(li)的(de)(de)氣體狀態統(tong)稱為(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)(kong)狀態下(xia)氣體稀薄程度(du)(du)(du)稱為(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)(kong)度(du)(du)(du)（degreeofvacuum），通常(chang)用(yong)(yong)壓(ya)力(li)值表示。因此真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)實(shi)際(ji)上不是完全真(zhen)(zhen)空(kong)(kong)(kong)(kong)的(de)(de)，采用(yong)(yong)真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)技術包(bao)裝(zhuang)的(de)(de)食(shi)品容器內的(de)(de)真(zhen)(zhen)空(kong)(kong)(kong)(kong)度(du)(du)(du)通常(chang)在600-1333Pa。所以，又(you)將真(zhen)(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)稱為(wei)(wei)減壓(ya)包(bao)裝(zhuang)或(huo)排氣包(bao)裝(zhuang)。