Simple past tense and past participle of board.(verb)
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Use "boarded" in a sentence
"Here, they again boarded a steam train to continue their trip to San Francisco."
"Sunlight peeked through cracks in boarded up windows."
"Henriques and Hein boarded Spanish ships off Cuba and seized shipments of New World gold and silver worth in today's dollars about the same as Disney's total box office for "Dead Man's Chest.""