The German getting strange, variable and unsteady (7)
I believe the answer is:
doddery
'unsteady' is the definition.
(similar in meaning)
'the german getting strange variable' is the wordplay.
'the german' becomes 'der' ('the' in German).
'getting' indicates putting letters inside.
'strange' becomes 'odd' (I've seen this in another clue).
'variable' becomes 'y' (algebra).
'der' going around 'odd' is 'dodder'.
'dodder'+'y'='DODDERY'
'and' is the link.
(Other definitions for doddery that I've seen before include "Old and infirm" , "Shaky" , "Unsteady in movement" , "Rather senile" , "Old and feeble" .)