真(zhen)空(kong)(kong)(kong)(kong)，這一(yi)術(shu)語(yu)譯自拉丁(ding)文vacuo，其意義是虛無。其實真(zhen)空(kong)(kong)(kong)(kong)應理解為(wei)氣體較稀薄的(de)(de)空(kong)(kong)(kong)(kong)間(jian)。在(zai)指定的(de)(de)空(kong)(kong)(kong)(kong)間(jian)內，低于一(yi)個大(da)氣壓力的(de)(de)氣體狀態統稱(cheng)(cheng)為(wei)真(zhen)空(kong)(kong)(kong)(kong)。真(zhen)空(kong)(kong)(kong)(kong)狀態下氣體稀薄程度(du)稱(cheng)(cheng)為(wei)真(zhen)空(kong)(kong)(kong)(kong)度(du)（degreeofvacuum），通(tong)常(chang)用(yong)壓力值(zhi)表示。因(yin)此真(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)(zhuang)實際上不是完(wan)全真(zhen)空(kong)(kong)(kong)(kong)的(de)(de)，采用(yong)真(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)(zhuang)技術(shu)包(bao)裝(zhuang)(zhuang)(zhuang)的(de)(de)食品(pin)容(rong)器內的(de)(de)真(zhen)空(kong)(kong)(kong)(kong)度(du)通(tong)常(chang)在(zai)600-1333Pa。所以(yi)，又將(jiang)真(zhen)空(kong)(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)(zhuang)稱(cheng)(cheng)為(wei)減壓包(bao)裝(zhuang)(zhuang)(zhuang)或(huo)排氣包(bao)裝(zhuang)(zhuang)(zhuang)。