'non-undulatory' is formed from the English prefix 'non-' (from Latin 'non', meaning 'not') combined with 'undulatory', which ultimately derives from Latin 'undulatus' (from 'unda' meaning 'wave').

'undulatory' comes via Latin 'undulatus' (past participle of 'undulare', to move in waves) into English as 'undulate' and the adjective 'undulatory'; the modern compound 'non-undulatory' is a productive English negation using the prefix 'non-'.

Initially related words like 'undulate' meant 'to move in waves'; 'non-undulatory' has developed straightforwardly to mean 'not having wave-like form or motion'.