κατάσκοπος

(prepositionally) down (in place or time), in varied relations (according to the case (genitive, dative or accusative) with which it is joined)

perhaps akin to G4626 (σκάπτω) through the idea of concealment; compare G4629 (σκέπασμα)); a watch (sentry or scout), i.e. (by implication) a goal