Glimpse sharp implement that goes up and down (6)
I believe the answer is:
seesaw
'up and down' is the definition.
(thesaurus)
'glimpse sharp implement that' is the wordplay.
I cannot really understand how this works, but
'glimpse' could be 'see' (I've seen this before) and 'see' is found in the answer.
'implement' could be 'saw' (saw is a kind of implement) and 'saw' is located in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'goes' is the link.
Can you help me to learn more?
(Other definitions for seesaw that I've seen before include "Children's up-and-down play structure" , "Vacillate; playground feature" , "Go one way and then the other" , "that has its ups and downs" , "Playground device" .)