From Longman Dictionary of Contemporary Englishgain timegain timeTIME/HAVE TIMEto deliberately do something to give yourself more time to think OPP lose time → gain
Examples from the Corpus
gain time• Dexter wondered if his vagueness was due to the shock of his wife's murder or an attempt to gain time.• I accepted a chair and asked for a glass of water instead of the brandy, trying to gain time.• "Well, let me see, " he said slowly, trying to gain time before answering the question.