Ambiguity can be defined as a form of communication with two or more possible meanings. In many cases, however, one interpretation is more likely than the other. Ambiguity can be further classified into structural and lexical.
An example of ambiguity which I recall from studying linguistics is "He saw the man with binoculars". This sentence has two possible interpretations. It may mean that the subject used binoculars to see the man. In this case, the prepositional phrase "with binoculars" is a verb complement. However, another interpretation is that the subject saw a man who had binoculars. In the case, "with binoculars" is part of the noun phrase, a noun adjunct.
The likely interpretation is that the subject used binoculars to see the man. However, the other interpretation is also possible. The intended meaning is usually clear from context. If not, it is possible to disambiguate so that the intended meaning is clear. The sentences "He used his binoculars to see the man" and "He saw the man who had binoculars" are not at all ambiguous.
The sentence "He saw the man with binoculars" is an example of structural ambiguity. The position of the prepositional phrase makes two interpretations possible. However, if the prepositional phrase is shifted to the beginning of the sentence, only one interpretation is possible. This is the case with "With binoculars he saw the man". Now the phrase "with binoculars" is the verb complement of "saw".
"She drew five triangles and squares" has many possible interpretations. One interpretation is that the subject drew five triangles and five squares. In this interpretation, ellipsis leaves out "five" before the object "squares". Another interpretation is that the subject drew five triangles and an undefined number of squares. Also possible is the interpretation that the subject drew a combination of triangles and squares that totalled five. The possibilities are three triangles and two squares and two triangles and three squares. Thus the sentence "She drew five triangles and squares" has four different interpretations.
Another kind of ambiguity is lexical. For example, the sentence "They sat by the bank" is ambiguous because of the word "bank". It can refer to either a financial institution or the edge of a body of water such as a river. From context, however, the meaning is usually very clear. The more likely interpretation in this case is that "bank" refers to the edge of a river than to a financial institution.
The sentence "The lamb is too hot to eat" is ambiguous because it is not clear whether "lamb" refers to the live animal or to meat on a plate. If the lamb is alive, the animal has no appetite but may be very thirsty. If the lamb is meat to be eaten, the person who wants to eat it must wait for it to cool down. Ambiguity also occurs with the word "hot" in the interpretation in which "lamb" refers to meat. In this case, "hot" may mean at a high temperature or spicy. Despite the ambiguity of "The lamb is too hot to eat", the likely interpretation is that the meat is either at too high a temperature or too spicy to eat.
Many examples of ambiguity can be found in language. However, communication is usually clear because the meaning can be understood from the context in which it is communicated. If the meaning is not clear, it becomes necessary to disambiguate.