inundate comes from Latin inundatus, past participle of inundare 'to overflow', from in- 'onto' plus undare 'to flow in waves', from unda 'wave'. Morphologically, the prefixed shape matters: the initial element belongs to the recorded formation and helps explain the modern form's surface analysis. In present English, the verb sense is "to flood or overwhelm with a great quantity", so the historical development ends in a clearly identifiable modern dictionary use. The same base also appears in related forms such as undulate, abundant, and redundant, and in derivatives such as inundation, inundator, and inundatory. Its semantic neighborhood includes flood, deluge, swamp, and overwhelm, which helps locate the modern sense without adding a separate etymological claim. The named historical forms include Latin inundare and Latin unda.