真(zhen)(zhen)空(kong)(kong)(kong)，這一(yi)(yi)術語譯自(zi)拉丁(ding)文vacuo，其意義是虛無(wu)。其實真(zhen)(zhen)空(kong)(kong)(kong)應(ying)理解為(wei)氣(qi)體較(jiao)稀薄(bo)的(de)(de)空(kong)(kong)(kong)間。在指定的(de)(de)空(kong)(kong)(kong)間內，低于一(yi)(yi)個大(da)氣(qi)壓(ya)力的(de)(de)氣(qi)體狀(zhuang)(zhuang)態統稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)。真(zhen)(zhen)空(kong)(kong)(kong)狀(zhuang)(zhuang)態下(xia)氣(qi)體稀薄(bo)程度稱(cheng)為(wei)真(zhen)(zhen)空(kong)(kong)(kong)度（degreeofvacuum），通常用壓(ya)力值表示。因(yin)此真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)實際上不是完全真(zhen)(zhen)空(kong)(kong)(kong)的(de)(de)，采用真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)技(ji)術包(bao)裝(zhuang)(zhuang)的(de)(de)食品容器內的(de)(de)真(zhen)(zhen)空(kong)(kong)(kong)度通常在600-1333Pa。所以(yi)，又將真(zhen)(zhen)空(kong)(kong)(kong)包(bao)裝(zhuang)(zhuang)稱(cheng)為(wei)減壓(ya)包(bao)裝(zhuang)(zhuang)或排氣(qi)包(bao)裝(zhuang)(zhuang)。