'antidynastically' originates from Greek elements: the prefix 'anti-' and the adjective-form root 'dynastikos' (from Greek 'dynastēs'), where 'anti-' meant 'against' and 'dynastikos' related to 'rule' or 'power'.

'antidynastically' changed from the Modern English adjective 'antidynastic' (itself formed from 'anti-' + 'dynastic', with 'dynastic' from 'dynasty') combined with the adverbial suffix '-ally', and eventually became the modern English adverb 'antidynastically'.

Initially, the components conveyed 'against a ruler/holding of power by a dynasty', but over time the formed word has come to mean more generally 'in a manner opposed to dynastic or hereditary rule'.