A polite phrase meaning “sorry to have kept you waiting” or used when handing something to someone who has been waiting (similar to 'sorry to have kept you').
お待ちどおさま、こちらがご注文のケーキです。
Sorry to have kept you waiting — here is the cake you ordered.
少々お待ちください、と店員が言った後にお待ちどおさまと料理を運んできた。
After the clerk said, 'Please wait a moment,' they brought the dish saying, 'Sorry to have kept you waiting.'
お待ちどおさま、と渡された封筒には領収書が入っていた。
When they handed me the envelope saying, 'Sorry to have kept you waiting,' it contained the receipt.