I travel, did you say? (4)
I believe the answer is:
rome
'i' is the definition.
Although both the answer and definition are singular nouns, I don't understand how one could define the other.
'travel did you say?' is the wordplay.
'travel' becomes 'roam' (roaming is a kind of travelling).
'did you say?' shows a homophone (sound like).
'roam' is a homophone of 'ROME'.
Can you help me to learn more?
(Other definitions for rome that I've seen before include "City not built in a day" , "Capital city" , "Where to emulate the locals" , "church" , "All roads lead to it" .)