The Oxford English dictionary bills itself as the definitive record of the English language.  The state library has copies downtown and Salt Lake/Moanalua.  If you have disposable income you can buy an annual subscription to the online version for $295.  For many years I used the compact version (which comes with a magnifying glass) but now find the online version much more useful.

Aloha from this Kailua HS class of '70 grad.