suzerain

n (fml 文) country or ruler that controls the foreign policy of another country but allows it to govern its own internal affairs 宗主国; 宗主国的统治者.

susceptible, suspect, suspect sb. of, suspend, suspended, suspended animation, suspender, suspender belt, suspenders, suspense, suspension, suspension bridge, suspicion, suspicious, suspiciously, suss, sustain, sustained, sustenance, suture, suzerainty, svelte, SW, swab, swaddle, swaddling-clothes, swag, swagger, swagger-stick (also `swagger-cane), swaggering, swaggeringly, swagman, swain, swallow, swallow up, swallow-dive (Brit) (US swan-dive), swam, swami, swamp, swampy,