劍橋詞典a type of cumulus (= a tall , rounded , white cloud with a flat base ) formed in a very thin layer and often in a regular pattern 卷積云（一種稀薄的高空云，由一系列規(guī)則排列的白云堆積形成,底部扁平） 比較altocumulus stratocumulus 返回 cirrocumulus