Could it be a tall building with a very small timepiece? (10)
I believe the answer is:
watchtower
'could it' is the definition.
I can't tell whether this definition defines the answer.
'a tall building with a very small timepiece?' is the wordplay.
'a tall building' becomes 'tower' (I've seen this before).
'with' says to put letters next to each other.
'a very small timepiece?' becomes 'watch' (I can't justify this - if you can you should give a lot more credence to this answer).
'tower' after 'watch' is 'WATCHTOWER'.
'be' acts as a link.
Can you help me to learn more?
(Other definitions for watchtower that I've seen before include "Lookout" , "giving lofty viewpoint" .)