Dotty punctuation mark? (5)
I believe the answer is:
colon
This could be a double definition.
'dotty punctuation' is the first definition.
'colon' can be an answer for 'punctuation' (colon is a kind of punctuation). I'm not certain of the 'dotty' bit.
'mark?' is the second definition.
(colon is a kind of mark)
Can you help me to learn more?
(Other definitions for colon that I've seen before include "Costa Rican currency" , "Punctuate part of the large intestine" , "Punctuation mark; gut" , "Stop (less than full)" , "Start of one canal" .)