lifeboat UK /ˈlaɪfˌbəʊt/US /ˈlaɪfˌboʊt/noun 2verb 1forms 3 noun2 •A boat especially designed for saving the lives of shipwrecked people or people in distress at sea (either launched from the shore with a crew, or else carried on board a larger ship).I've got a watch that turns into a lifeboat — 1971 •An emergency vehicle carried aboard a spaceship. verb1 •To rescue; to carry to safety formslifeboated · lifeboating · lifeboats