OUR-LADY'S-THISTLE Meaning of OUR-LADY'S-THISTLE in English ̷ ̷ˈ ̷ ̷ ̷ ̷ˈ ̷ ̷ ̷ ̷ nounUsage: usually capitalized O&L: milk thistle 1 Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012