Siknesse, s. sickness, 2295.
Silf, adj. same, like, 2020.
Silogisme, s. syllogism, 4457.
Similacioun, s. dissimulation, C 7230.
Simonye, s. simony, C 7029.
Simpilly, adv. simply (Northern), 4510. (Miswritten simply.)
Simplesse, s. Simplicity (the name of an arrow), 1774; simplicity, C 6381.
Sire, s. father; sire ne dame, neither father nor mother, C 5887.
Sith, conj. since, 1964, 4367, C 6266.
Sithen, adv. afterwards, 1999, C 7130.