Faithful without pretence (5)
I believe the answer is:
exact
'faithful' is the definition.
(as in a faithful translation)
'without pretence' is the wordplay.
'without' becomes 'ex' (Latin).
'pretence' becomes 'act'.
'ex'+'act'='EXACT'
(Other definitions for exact that I've seen before include "Precise, accurate" , "Completely accurate" , "Correct; insist on" , "Strict" , "Not approximate, precise" .)