/ˈwɔ:tətaɪt ||; ˈwɔtɚˈtaɪt/adj1 made so that water cannot get in or out 不渗水的;不透水的: a watertight container 不透水的容器
2 (used about an excuse, opinion, etc) impossible to show to be wrong; without any faults (指借口、看法等)没有漏洞的,毫无破绽的: His alibi was absolutely watertight. 案发时他不在现场的证据毫无破绽。