真(zhen)空(kong)(kong)(kong)，這一術語(yu)譯自拉丁文vacuo，其意(yi)義是虛(xu)無。其實(shi)真(zhen)空(kong)(kong)(kong)應(ying)理解為(wei)氣(qi)體較(jiao)稀(xi)薄的空(kong)(kong)(kong)間(jian)。在(zai)指定的空(kong)(kong)(kong)間(jian)內，低(di)于一個(ge)大氣(qi)壓力的氣(qi)體狀態(tai)統稱(cheng)(cheng)為(wei)真(zhen)空(kong)(kong)(kong)。真(zhen)空(kong)(kong)(kong)狀態(tai)下氣(qi)體稀(xi)薄程度稱(cheng)(cheng)為(wei)真(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通(tong)常用壓力值表示。因(yin)此真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)實(shi)際(ji)上(shang)不是完全(quan)真(zhen)空(kong)(kong)(kong)的，采用真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)技術包(bao)裝(zhuang)(zhuang)的食(shi)品容器內的真(zhen)空(kong)(kong)(kong)度通(tong)常在(zai)600-1333Pa。所以，又將真(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)稱(cheng)(cheng)為(wei)減壓包(bao)裝(zhuang)(zhuang)或排氣(qi)包(bao)裝(zhuang)(zhuang)。