Okay! So it turns out I was missing something obvious!
For those that don't know - You set the fields visible in the word list (i.e. the columns) in Gnosis > Options > Words - then under "Field Order" you define the fields you wish to show. (there is a handy tooltip explaining this!)
Field Order
Which fields to include in the list, and in what order, in comma separated numbers.
0 --- word
1 --- pronounciation
2 --- category
3 --- definition
4 --- added by
5 --- date created
6 --- date modified
7 --- tags
8 ---source
For example; To show just the word and definition, enter 0, 3