'over-meticulous' is a compound formed from the prefix 'over-' (meaning 'excessive' or 'beyond') and the adjective 'meticulous', which ultimately comes from Latin 'meticulosus' (from 'metus' meaning 'fear').

'over-' originates in Old English 'ofer' meaning 'above, beyond, excessive', and was productive as a prefix in Modern English. 'Meticulous' entered English in the late 16th to early 17th century from Latin 'meticulosus' (via scholarly/learned use), and the compound 'over-meticulous' developed by combining the productive English prefix 'over-' with the established adjective 'meticulous'.

'Meticulosus' in Latin originally meant 'fearful' or 'full of fear'; by the time it entered English as 'meticulous' its sense shifted toward 'careful, attentive to small details.' The compound 'over-meticulous' narrows that further to indicate an excessive degree of such carefulness.