From Longman Dictionary of Contemporary Englishdo something for luckdo something for luckLUCKYto do something because you think it might bring you good luck She crossed her fingers for luck. → luck
Examples from the Corpus
do something for luck• John always carried a rabbit's foot for luck.• An extra teaspoonful for luck could well be disaster.• By now the only part of Mr. Rainsford's brewery left standing was the taproom kept for luck like an old horseshoe.• Certainly there may be the odd chart or graph thrown in for luck but the basic requirement is for high quality text.• I gave him one for luck on the back of his neck.• Is he the kind of man to lend you the rings for luck for a short time?• Now he gave it one last violent shake for luck.• One for luck, and farewell. 