Surely and firmly the lady ties a knot (8)
I believe the answer is:
steadily
'surely' is the definition.
(thesaurus)
'lady ties a knot' is the wordplay.
'a knot' is an anagram indicator (I've seen 'knotted' mean this).
'lady'+'ties'='ladyties'
'ladyties' anagrammed gives 'STEADILY'.
'and firmly the' acts as a link.
This may not be right. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for steadily that I've seen before include "In unfaltering manner" , "At a regular pace" , "Regularly, without fluctuation" , "Regularly, constantly" , "Surely and regularly" .)