Lewis & Short

spectĭo, ōnis, f. [specio], in the lang. of augurs, an observing of the auspices; hence, also, the right of observing them (which belonged to the magistrates), Varr. L. L. 6, § 82 Müll.; Cic. Phil. 2, 32, 81; Fest. s. h. v. p. 333.