Dora set out with a note of anchorage (9)
I believe the answer is:
roadstead
'anchorage' is the definition.
(roadstead is a kind of anchorage)
'dora set out with a note' is the wordplay.
'out with' indicates an anagram (out can mean wrong or inaccurate).
'note' becomes 'd' (musical note).
'dora'+'set'='doraset'
'doraset' anagrammed with 'a' makes 'roadstea'.
'roadstea'+'d'='ROADSTEAD'
'of' acts as a link.
(Other definitions for roadstead that I've seen before include "Sheltered spot where ships may ride at anchor" , "Sheltered stretch of water for anchoring ships" , "anchorage" .)