Here is one I haven’t heard for years.
cog·i·tate
[koj-i-teyt]
VERB (USED WITHOUT OBJECT) [COG·I·TAT·ED, COG·I·TAT·ING.]
1.
to think hard; ponder; meditate: to cogitate about a problem.
VERB (USED WITH OBJECT) [COG·I·TAT·ED, COG·I·TAT·ING.]
2.
to think about; devise: to cogitate a scheme.

It slipped into my mind today as I was contemplating the books I have just read and that I now intend to review after a time spent cogitating them. It is a word that describes exactly the process being undergone. If there is a modern word that is better, then I cannot recollect it.

Why is it words go out of usage? Sometimes it is because of a grandeur of presence no longer needed in this world of the instant fix. Sometimes it is because of the word coming from a foreign language, such as legerdemain, a wonderful world conjuring up the impossible. Somehow it doesn’t sound the same with the modern translation of ‘slight of hand’.

Will I try to resurrect cogitate in one of my books? Nope. I leave that to those who write literary fiction. I have no intention of raising speed bumps in stories that have people catapulted out of the world I have worked really hard to bring alive because they need to find a darn dictionary. In the meantime, I will continue with my cogitation.