Primitive Red Army unit out of position (11)
I believe the answer is:
rudimentary
'primitive' is the definition.
(I've seen this before)
'red army unit out of position' is the wordplay.
'out of position' indicates anagramming the letters.
'red'+'army'+'unit'='redarmyunit'
'redarmyunit' anagrammed gives 'RUDIMENTARY'.
(Other definitions for rudimentary that I've seen before include "in the early stages" , "Limited to basics" , "Basic" , "Undeveloped" , "Primitive" .)