• Etymology Today from M-W: vagary \VAY-guh-ree\
: an erratic, unpredictable, or extravagant manifestation, action, or notion

In the 16th century, if you "made a vagary" you took a wandering journey, or you figuratively wandered from a correct path by committing some minor offence. If you spoke or wrote vagaries, you wandered from a main subject. These senses hadn't strayed far from their origin, since "vagary" is probably based on Latin "vagari," which means "to wander." Indeed, in the 16th and 17th centuries there was even an English verb "vagary" that meant "to wander." Nowadays, the noun "vagary" is mostly used in its plural form, and vagaries have more to do with unpredictability than with wandering.

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