Synonyms to penetrating eye

eagle eye, X-ray eye, custodianship, custody, eye, gimlet eye, guard, guardedness, guardianship, invigilation, keen eye, lookout, monitoring, observance, peeled eye, proctoring, prudence, qui vive, scrutiny, sharp eye, stewardship, surveillance, tab, vigil, vigilance, wariness, watch, watch and ward, watchful eye, watchfulness, watching, weather eye, cover, defense, lee, preservation, protection, protective custody, refuge, safekeeping, safety, shade, shadow, shelter