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"
beyond and outside the ordinary range of human experience or understanding; "philosophers...often explicitly reject the notion of any transcendent reality beyond thought...and claim to be concerned only with thought itself..."- W.P.Alston; "the unknowable mysteries of life"
exceeding or surpassing usual limits especially in excellence
the flash of light that accompanies an electric discharge in the atmosphere (or something resembling such a flash); can scintillate for a second or more
abrupt electric discharge from cloud to cloud or from cloud to earth accompanied by the emission of light
singled out for notice or especially for a dire fate; "a marked man"
strongly marked; easily noticeable; "walked with a marked limp"; "a pronounced flavor of cinnamon"
having or as if having an identifying mark or a mark as specified; often used in combination; "played with marked cards"; "a scar-marked face"; "well-marked roads"
one of several parallel layers of material arranged one on top of another (such as a layer of tissue or cells in an organism or a layer of sedimentary rock)