ETYMOLOGY is the 4th section in the Advanced pop-up's menu. The Advanced pop-up is exclusive to the Premium Chinese Add-on that you purchase.
What's in it?
In Etymology, you will find:
(1) FORMATION: Formation type - the way this Chinese character was originally formed
(2) DECOMPOSITION: Breaking down components to the most basic radicals
(3) COMPONENT OF: A list of Chinese words that share this character as a phonetic element (which gives these words their original sounds) or non-phonetic (giving meanings, etc)