真(zhen)(zhen)空(kong)(kong)(kong)，這一術(shu)語譯(yi)自拉(la)丁文(wen)vacuo，其(qi)意義(yi)是(shi)虛無(wu)。其(qi)實真(zhen)(zhen)空(kong)(kong)(kong)應理(li)解(jie)為(wei)(wei)(wei)氣(qi)(qi)(qi)體較稀薄的(de)(de)空(kong)(kong)(kong)間(jian)。在(zai)指定的(de)(de)空(kong)(kong)(kong)間(jian)內，低于一個(ge)大(da)氣(qi)(qi)(qi)壓力的(de)(de)氣(qi)(qi)(qi)體狀態統稱(cheng)為(wei)(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀態下氣(qi)(qi)(qi)體稀薄程度(du)稱(cheng)為(wei)(wei)(wei)真(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常用壓力值表示。因此真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)(bao)裝(zhuang)(zhuang)實際上不是(shi)完全真(zhen)(zhen)空(kong)(kong)(kong)的(de)(de)，采用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)(bao)裝(zhuang)(zhuang)技(ji)術(shu)包(bao)(bao)(bao)裝(zhuang)(zhuang)的(de)(de)食品容器(qi)內的(de)(de)真(zhen)(zhen)空(kong)(kong)(kong)度(du)通(tong)常在(zai)600-1333Pa。所以(yi)，又將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)(bao)裝(zhuang)(zhuang)稱(cheng)為(wei)(wei)(wei)減壓包(bao)(bao)(bao)裝(zhuang)(zhuang)或排(pai)氣(qi)(qi)(qi)包(bao)(bao)(bao)裝(zhuang)(zhuang)。