E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
(1) Hoity-toity spirits means high spirits, extremely elated and flighty. Selden, in his Table Talk, says: In Queen Elizabeths time gravity and state were kept up but in King Charless time there was nothing but Frenchmore [French manners] tolly-polly, and hoit-comme-toit, where hoit comme toit means flightness.
(2) As an exclamation of reproof it means, Your imagination or spirits are running out of all bounds; hoit-a-toit! hity-tity! Hoity-toity! What have I to do with dreams? (Congreve.)
We have the verb to hoit = to assume; to be elated in spirits, and perhaps hoity-toity is only one of those words with which our language abounds;
as, harum-scarum, titty-totty, namby-pamby, hugger-mugger, fiddle-faddle, and scores of others.