Baxter-Sagart 2014 reconstruct 夏 *[g]ˤraʔ > haeH > xià ‘summer’ (~ *[g]ˤraʔ-s). A homophone is 暇 *[g]ˤra-s > haeH > xià ‘leisure’, with a probable cognate in Written Burmese: â ‘vacant, free; disengaged’. In the two or three months it takes the millets to grow, set ears and ripen, between early summer and harvesting in late summer or autumn, a period of (relative) calm sets in. It would make sense if that period was called ‘leisure’: that would later become the name of summer.
Cite this post as: Laurent Sagart, "Chinese 夏 ‘summer’: time of leisure ?," in Sino-Tibetan-Austronesian, 11/02/2023, https://stan.hypotheses.org/2246.