It’s the Word of the Day at Merriam-Webster today, so here is context clues worksheet on the adjective desultory. It means, for the purposes of making meaning on this document, and in the vernacular as well, “marked by lack of definite plan, regularity, or purpose.”
However, it can also mean “not connected with the main subject” and “disappointing in progress, performance, or quality.” This is not a high-frequency word in English, and in any case, I don’t know that I’ve ever seen or heard it used to mean “not connected to the main subject.” On the other hand, “disappointing in progress, performance, or quality” is a close enough corollary to “marked by lack of definite plan, regularity, or purpose that one might say the first definition is the outcome of the second in this sentence.
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