1. a looking out, watch, guard , as a duty, (Herdotus Historicus); φρουρὰν ἄζηλον ὀχήσω shall keep unenviable watch , (Aeschulus Tragicus); φρουρὰ ὄμματος my watchful eye, (Sophocles Tragicus); φρουρᾶς ᾄδειν to sing while on guard , (Aristophanes Comicus)

2. a prison , (Plato Philosophus)

3. of persons, a watch, guard, garrison , (Herdotus Historicus), etc.; especially of frontier-posts , which were guarded in Attica by the περίπολοι, (Xenophon Historicus)

4. at Sparta, a body of men destined for service , φρουρὰν φαίνειν (see. φαίνω A. 1. 5). (ML)