I have a 2013 MacbookPro running OS X 10.9.2, and up-to-date Chrome (Version 35.0.1916.114).
When using three finger tap to look up a word with dictionary in Chrome (when chosen in the trackpad settings), the definition often pops up high above the placement of the word. Other times, it doesn't work at all, and sometimes it works like it should.
I have seen other questions here dealing with it not working, but not with its placement.
Pictured below is how it often looks. The word I looked up can be seen at the bottom.
Best Answer
The word needs to be in about 1 inch from top or bottom of the screen for pop up to work.
It wont work on all type of web pages.
Here is a example of the pop up relative to the position of the word on the sceen.
The word "Bittersweet" is Up most position for the pop up to work
Mid screen
Low, in this case you actually can see the word in the sentence and the pop up is above it.