'undented' originates from English, specifically formed from the prefix 'un-' (meaning 'not') combined with 'dented' (from 'dent'). The word 'dent' itself comes from Old French 'dent' and ultimately Latin 'dens, dent-' meaning 'tooth' (used for a tooth-like notch or indentation).

'dented' developed in Middle English from Old French 'dent' (meaning 'tooth' or 'tooth-like notch'); the adjective 'undented' was formed in English by applying the productive prefix 'un-' to the past-participial/adjectival form 'dented' (and using the suffix '-ed').

Initially 'dent' related literally to 'tooth' (Latin 'dens'), then shifted to mean a notch or depression; 'dented' meant 'having a depression,' and 'undented' came to mean 'not having such a depression' or 'not dented.'