For a real logophile, I find that I bump into certain words like roadblocks and, even when I can wrap my mind around the definition, my thought process grinds to a halt until I can process that particular word. An example is the word stochastic. I twig to the idea that it means "random" but what is it that necessitates its use instead of the word 'random?' This comes from a dyed-in-the-wool sesquipedalian as well.
"Quondam" is another one of those words. I should come up with a name for this phenomenon.