Entry 3 senses · 2 variants Webster, 1913 Sib /(sĭb)/ · IPA /sɪb/ n. a. 01 n. A blood relation. 1. A blood relation.[Obs.] 2. a sibling. See: sibling 02 a. Related by blood; akin. 1. Related by blood; akin.[Obs. or Prov. Eng. & Scot.] “Your kindred is but . . . little sib to you.” — Chaucer. “[He] is no fairy birn, ne sib at all To elfs, but sprung of seed terrestrial.” — Spenser.