Silicic \Si*lic"ic\, a. [L. silex, silicis, a flint: cf. F. silicique.] (Chem.) Pertaining to, derived from, or resembling, silica; specifically, designating compounds of silicon; as, silicic acid. {Silicic acid} (Chem.), an amorphous gelatinous substance, {Si(HO)4}, very unstable and easily dried to silica, but forming many stable salts; -- called also {orthosilicic, or normal silicic, acid}.