First found in motionless figure (9)
I believe the answer is:
statistic
'figure' is the definition.
(statistics are figures)
'first found in motionless' is the wordplay.
'first' becomes 'ist' (ist resembles 1st).
'found in' indicates putting letters inside.
'motionless' becomes 'static' (synonyms).
'ist' put inside 'static' is 'STATISTIC'.
(Other definitions for statistic that I've seen before include "part of a table perhaps" , "Numerical fact" , "E.g. crime figure" , "It could be vital" , "One single item of data" .)