expatiate (v. ek-SPAY-shee-ayt)

1 : to move about freely or at will : wander

2 : to speak or write at length or in detail

The Latin antecedent of expatiate is exspatiari, which combines the prefix ex- (out of) with spatiari (to take a walk), itself from spatium (space or course). Exspatiari means to wander from a course, and in the figurative sense, to digress. But when English speakers began using expatiate in 1538, we took wander as simply to move about freely. In a similar digression from the original Latin, we began using expatiate in a figurative sense of to speak at length. That's the sense of the word most often used these days, usually in combination with on or upon.

superannuated (adj. soo-per-AN-yuh-wayt-id)

: incapacitated or disqualified for active duty by

advanced age

Superannuated was first put to use in English in the 1600s, having been borrowed from Medieval Latin superannuatus, past participle of superannuari (to be too old) -- from Latin super- (over or above) and annus (year). Shortly thereafter, we made our own verb, superannuate, from the adjective. Superannuate meant to pension off as well as to declare obsolete, meanings that are still in active service. Thus superannuated, the verb's past participle, can also mean both retired on a pension and obsolete. Superannuated can be a good word for referring to something (or someone) that has outlived its usefulness (such as a drawerful of superannuated neckties).