Noticed a blade (3)
I believe the answer is:
saw
This clue might be a double definition.
'noticed' is the first definition.
(I've seen this in another clue)
'a blade' is the second definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps you can see a link between them that I don't see?
Can you help me to learn more?
(Other definitions for saw that I've seen before include "Witnessed" , "Perceived visually" , "Old saying - cutting kind" , "Spotted" , "Grasped" .)