Used to tell fortune with old salt and turbot tails (5)
I believe the answer is:
tarot
'used to tell fortune' is the definition.
I can't tell whether this defines the answer.
'with old salt and turbot tails' is the wordplay.
'with' is an insertion indicator.
'old' becomes 'o' (abbreviation).
'salt' becomes 'tar' (both can informally mean a sailor).
'and' says to put letters next to each other.
'tails' suggests the final letters (I've seen 'tailed' mean this).
The last letter of 'turbot' is 't'.
'tar'+'t'='tart'
'o' put into 'tart' is 'TAROT'.
Can you help me to learn more?
(Other definitions for tarot that I've seen before include "Playing cards" , "one may have been taken from deck" , "Fortune teller" , "Set of cards used by fortune-tellers" , "These cards are used by fortune tellers" .)