Short book Croatia translated, about performing as a gymnast (9)
I believe the answer is:
acrobatic
'performing as a gymnast' is the definition.
I can't judge whether this defines the answer.
'short book croatia translated about' is the wordplay.
'short book' becomes 'b' (abbreviation for book; 'short' indicates a short form).
'translated' indicates anagramming the letters.
'about' becomes 'c' (abbreviation for circa).
'b'+'croatia'='bcroatia'
'bcroatia' with letters rearranged gives 'acrobati'.
'acrobati'+'c'='ACROBATIC'
Can you help me to learn more?
(Other definitions for acrobatic that I've seen before include "circus performer?" , "Involving physical agility" , "Like a gymnastic entertainer" , "spectacularly agile" , "Like a spectacular gymnast" .)