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.