Sailor held back by soldiers gets free (6)
I believe the answer is:
gratis
'free' is the definition.
(synonyms)
'sailor held back by soldiers' is the wordplay.
'sailor' becomes 'gris' (I am not sure about this - if you are sure you should believe this answer much more).
'held' means one lot of letters goes inside another.
'back by' is a reversal indicator.
'soldiers' becomes 'TA' (abbreviation for Territorial Army).
'ta' in reverse letter order is 'at'.
'gris' enclosing 'at' is 'GRATIS'.
'gets' is the link.
Can you help me to learn more?
(Other definitions for gratis that I've seen before include "not charged" , "Free of charge" , "Without payment" , "On the house" , "Free, at no cost" .)