1570s, from Middle French sentinelle (16c.), from Italian sentinella "a sentinel." OED says "No convincing etymology of the It. word has been proposed," but perhaps (via a notion of "perceive, watch"), from sentire "to hear," from Latin sentire "feel, perceive by the senses" (see sense (n.)).
权威例句
1. a tall round tower standing sentinel over the river
镇守在河边的一座高高的圆塔
2. We gave the watchword, and the sentinel let us pass.
我们说出口令, 哨兵就把我们放过去了.
3. The lone sentinel walked toward his post.
忧愁的哨兵走向岗哨.
4. SENTINEL? Model 880 source projectors are portable, lightweight and compact industrial radiographic exposure devices.