真(zhen)(zhen)空(kong)(kong)(kong)，這一術語譯自拉丁文vacuo，其意(yi)義是(shi)虛無。其實(shi)(shi)真(zhen)(zhen)空(kong)(kong)(kong)應(ying)理解為(wei)氣(qi)體(ti)較稀薄的空(kong)(kong)(kong)間(jian)。在指定(ding)的空(kong)(kong)(kong)間(jian)內，低于一個大氣(qi)壓力的氣(qi)體(ti)狀態統稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀態下氣(qi)體(ti)稀薄程度(du)稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常用壓力值表示。因此(ci)真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝實(shi)(shi)際(ji)上不是(shi)完(wan)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(shi)品容器內的真(zhen)(zhen)空(kong)(kong)(kong)度(du)通(tong)常在600-1333Pa。所以，又(you)將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)(bao)裝稱(cheng)為(wei)減(jian)壓包(bao)(bao)裝或(huo)排(pai)氣(qi)包(bao)(bao)裝。