 Ambiguity is generally taken to be a property enjoyed by signs that bear multiple (legitimate) interpretations in a language or, more generally, some system of signs.  ’legitimate’ is a cover term I’m using to nod to the fact that many signs can, in principle, bear just about any interpretation.  The relativization is to prevent ambiguity in terms like like ‘leaped’ which means leaped in English but loved in German.  In common parlance, the word ‘ambiguity’ is used loosely: often simple underspecificity will suffice for a charge of ambiguity. The U.S.’s policy towards the unification of China and Taiwan has been described as a policy of ‘strategic ambiguity’, one that allows the U.S. to be non-specific with respect to the status of Taiwan. ‘Jane’s sister will come to visit’ is sometimes thought to be ambiguous when Jane has multiple sisters. A movie with a character that heads to surgery at the end, leaving it open whether he lives or dies, is said to have an ambiguous ending. There is a medical condition known as ‘ambiguous genitalia’ in which the genitals don’t categorize clearly, or exclusively, into male or female genitalia.