Whoa--no luck yet on séant, but look what I found during the search--check out the last def.:
season - 13c., from O.Fr. saison "a sowing, planting," from L. sationem (nom. satio) "a sowing," from pp. stem of serere "to sow" (see sow). Sense shifted in V.L. from "act of sowing" to "time of sowing." The verb meaning "improve the flavor of by adding spices" is c.1390, from O.Fr. assaisoner "to ripen, season," on the notion of fruit becoming more palatable as it ripens. Applied to timber by 1540. In 16c., it also meant "to copulate with." Seasoning (n.) is from 1580.

http://www.etymonline.com/s3etym.htm