There's trouble after soldiers back a visitor (9)
I believe the answer is:
sightseer
'a visitor' is the definition.
The answer and definition can be both people as well as being singular nouns.
Maybe there's a link between them I don't understand?
'there's trouble after soldiers back' is the wordplay.
'trouble' indicates anagramming the letters.
'after' says to put letters next to each other.
'soldiers' becomes 'gis' (GI is an informal term for a US soldier).
'back' is a reversal indicator.
'gis' reversed gives 'sig'.
'theres' is an anagram of 'htseer'.
'htseer' put after 'sig' is 'SIGHTSEER'.
Can you help me to learn more?
(Other definitions for sightseer that I've seen before include "Tripper" , "Visitor to famous locations" , "Tourist visiting scenes of interest" , "Rubberneck" .)