'astatize' originates from New Latin/scientific coinage ultimately built from Greek 'astatos', where 'a-' meant 'not' and 'statos' (from 'histemi' / 'statos') meant 'standing'.

'astatos' (Greek) passed into New Latin/Modern Latin formations (e.g. 'astaticus') and then entered English as the adjective 'astatic'; the verb 'astatize' was later formed in scientific English from that adjective and produced the gerund 'astatizing'.

Initially the root meant 'not standing' or 'unstable'; in scientific English it evolved to refer specifically to removing or cancelling restoring forces in magnetic or mechanical instruments—i.e., making them 'astatic'.