Oddball touching a double-edged sword (5)

I believe the answer is:

blade

I'm a little stuck... Click here to teach me more about this clue!

'sword' is the definition.
(I know that sword can be written as blade)

I don't understand the rest of the clue.

(Other definitions for blade that I've seen before include "Flat part of an oar" , "Sword" , "See 24 Across" , "A knife, or a dashing fellow" , "Leaf, of grass, say" .)

I've seen this clue in the Sydney Morning Herald.

Want a hint initially instead of a full solution? Install my app