mid-13c., egtetenþe, modified, by influence of eighteen, from Old English eahtateoða; from eight + teoða "tenth" (see -ty (1)). Cognate with German achtzehnte, Danish attende, Swedish adertonde.
eidetic
eidolon
Eiffel Tower
eight
eighteen
eighteenth
eightfold
eighth
eighties
eighty
eighty-six
