Simple past tense and past participle of preregister.(verb)
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Use "preregistered" in a sentence
"I believe people who preregistered had the opportunity to buy Tauntaun sleeping bags from Think Geek."
"The city specifically emailed couples who preregistered online, alerting them about the lottery, an aide to the mayor said."
"Not only did Plainfield's representative fail to show at the mandatory 'bidder's conference' in Trenton in May, to which the City was preregistered, but Mayor Robinson-Briggs has not made any public comment on why she is not supporting Plainfield's participation."