“Sith” appears in Middle and Early Modern English as a variant of “since,” used in logical or temporal clauses (“sith thou art gone”). It features in Chaucer and Spenser to maintain period syntax and rhythmic flow. Though obsolete, it adds historical authenticity to poetic reasoning, linking cause and effect with archaic concision.

Sith is an archaic conjunction meaning "since," "because," or "seeing that." It appears mainly in medieval and Renaissance texts, already archaic by Shakespeare's time. Chaucer uses sith frequently: "Sith you are so wise." Spenser employs it for deliberate archaism. Students should recognize sith as causal or temporal conjunction. The etymology connects to "since" (both from Old English siththan). In poetry, sith provides metrical alternative to "since," though its archaic quality is marked. By the 17th century, sith was fading except in conscious medievalism. Modern readers encounter sith mainly in Chaucer, Spenser, and their imitators. Understanding sith helps parse causal and temporal relationships in Middle English and deliberately archaic texts. The term sometimes appears as "sithen" or "sithence." Distinguishing sith (conjunction) from "since" (modern equivalent) helps decode archaic syntax.