Simple past tense and past participle of sentinel.(verb)
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Use "sentineled" in a sentence
"She led me through a foyer with Greek and Roman sculptures into a large library decorated with sets of antique books and out the back door to a swimming pool big enough to scrub down a herd of cattle and sentineled by topiary sculptures the size of radar dishes."
"It was black or dark like tar, and sentineled to the east and north by tall, dark pines — the serried spears of armed and watchful giants, as they now seemed to him — ogres almost — so gloomy, suspicious and fantastically erratic was his own mood in regard to all this."
"Along the West Bluff Road, Washington and Second Streets, they finally made their way across the Hannibal Bridge to Harlem, and from thence along the winding and hill-sentineled river road to Randolph"