(figurative) a course of action that is unproductive and offers no hope of improvement; "all the clues led the police into blind alleys"; "so far every road that we've been down has turned out to be a blind alley"
brought from wildness into a domesticated state; "tame animals"; "fields of tame blueberries"
very restrained or quiet; "a tame Christmas party"; "she was one of the tamest and most abject creatures imaginable with no will or power to act but as directed"
being or affecting or concerned with a surface; not deep or penetrating emotionally or intellectually; "superficial similarities"; "a superficial mind"; "his thinking was superficial and fuzzy"; "superficial knowledge"; "the superficial report didn't give the true picture"; "only superficial differences"
of little substance or significance; "a few superficial editorial changes"; "only trivial objections"
relating to a surface; "superficial measurements"; "the superficial area of the wall"
a measuring instrument that sends out an acoustic pulse in water and measures distances in terms of the time for the echo of the pulse to return; "sonar is an acronym for sound navigation ranging"; "asdic is an acronym for antisubmarine detection investigation committee"