simple past tense and past participle of accustom
"After years of waking up at four in the morning, she had become accustomed to the early start."
commonly used or practiced; usual
"his accustomed thoroughness"
"took his customary morning walk"
"his habitual comment"
"with her wonted candor"
Familiar with something through repeated experience; adapted to existing conditions.
"After living in the city for five years, she was accustomed to the constant noise of traffic and construction."
The word comes from the verb accustom, which means to make someone used to something, combined with the past tense suffix -ed. It originally described the act of training or habituating a person or animal to a specific condition.