sonar

n [U] device or system for detecting and locating objects under water by means of reflected sound waves 声纳装置; 声纳系统. Cf 参看 radar.

someone, someplace, somersault, something, something else, something like, something of, sometime, sometimes, someway, somewhat, somewhere, somnambulism, somnambulist, somnolence, somnolent, somnolently, son, son et lumiere, son-in-law, sonata, song, song-book, songbird, songster, songstress, songwriter, sonic, sonic barrier, sonic boom, sonnet, sonny, sonority, sonorous, sonorously, soon, sooner or later, soot, soothe, soothing,