Similar entries occur in previous lexica, including Hesychius and the Lexica Segueriana. Both headword and gloss are derived in the same way from a stem of the same verb (present stem vs. aorist stem, respectively), but their attested usage offers little support for the notion that they can be synonymous (see LSJ: Web address 1 (ἑκτικός ) and Web address 2 (σχετικός )). In fact, passages like Philo Judaeus, On Allegorical Interpretation 3.210 suggest that the opposite is more common.
cf. sigma 1781.