The ivories, as tickled (4)
I believe the answer is:
keys
'the ivories' is the definition.
(I've seen this in another clue)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for keys that I've seen before include "Bunch of openers?" , "Low islands, sycamore fruits" , "Islands; piano parts" , "Lockers" , "'Unlockers'" .)