真(zhen)(zhen)(zhen)空(kong)(kong)(kong)，這一術語譯自拉丁(ding)文vacuo，其(qi)意(yi)義是虛無。其(qi)實(shi)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)應理解為(wei)(wei)(wei)氣(qi)體較(jiao)稀薄的(de)空(kong)(kong)(kong)間。在(zai)(zai)指定的(de)空(kong)(kong)(kong)間內，低(di)于一個(ge)大氣(qi)壓力(li)的(de)氣(qi)體狀(zhuang)態(tai)統稱(cheng)為(wei)(wei)(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)態(tai)下氣(qi)體稀薄程度(du)稱(cheng)為(wei)(wei)(wei)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常(chang)用壓力(li)值表示。因此(ci)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)實(shi)際上不是完全真(zhen)(zhen)(zhen)空(kong)(kong)(kong)的(de)，采用真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)技術包(bao)(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)通(tong)常(chang)在(zai)(zai)600-1333Pa。所以，又將(jiang)真(zhen)(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝(zhuang)稱(cheng)為(wei)(wei)(wei)減壓包(bao)(bao)裝(zhuang)或排氣(qi)包(bao)(bao)裝(zhuang)。