真(zhen)(zhen)空(kong)(kong)(kong)，這(zhe)一術語譯自(zi)拉丁(ding)文(wen)vacuo，其意(yi)義是虛無。其實(shi)真(zhen)(zhen)空(kong)(kong)(kong)應理(li)解為(wei)氣(qi)(qi)體(ti)較稀薄(bo)的空(kong)(kong)(kong)間。在指定的空(kong)(kong)(kong)間內(nei)(nei)，低(di)于一個(ge)大氣(qi)(qi)壓(ya)力的氣(qi)(qi)體(ti)狀(zhuang)態(tai)統稱為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)態(tai)下氣(qi)(qi)體(ti)稀薄(bo)程度(du)(du)稱為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度(du)(du)（degreeofvacuum），通(tong)(tong)常用壓(ya)力值(zhi)表(biao)示(shi)。因(yin)此真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝實(shi)際上(shang)不是完全真(zhen)(zhen)空(kong)(kong)(kong)的，采(cai)用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝技術包(bao)(bao)裝的食品(pin)容(rong)器(qi)內(nei)(nei)的真(zhen)(zhen)空(kong)(kong)(kong)度(du)(du)通(tong)(tong)常在600-1333Pa。所以，又(you)將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝稱為(wei)減(jian)壓(ya)包(bao)(bao)裝或排氣(qi)(qi)包(bao)(bao)裝。