Pomeranian swimmer named Mark? (5)
I believe the answer is:
spitz
'pomeranian' is the definition.
The answer and definition can be both animals as well as being singular nouns.
Maybe you can see a link between them that I don't see?
'swimmer named mark?' is the wordplay.
I cannot really see how this works, but
'mark?' could be 'pit' ('pit' can be a synonym of 'mark') and 'pit' is located in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for spitz that I've seen before include "Little dog" , "Pomeranian dog" , "eg Samoyed" , "Mark --, US swimmer" .)