Lexical ambiguity is contrasted with
semantic ambiguity. The former represents a choice between a finite number of known and meaningful
context-dependent interpretations. The latter represents a choice between any number of possible interpretations, none of which may have a standard agreed-upon meaning. This form of ambiguity is closely related to
vagueness. Ambiguity in human language is argued to reflect principles of efficient communication. Languages that communicate efficiently will avoid sending information that is redundant with information provided in the context. This can be shown mathematically to result in a system that is ambiguous when context is neglected. In this way, ambiguity is viewed as a generally useful feature of a linguistic system. Linguistic ambiguity
can be a problem in law, because the interpretation of written documents and oral agreements is often of paramount importance.
Lexical ambiguity The
lexical ambiguity of a word or phrase applies to it having more than one meaning in the language to which the word belongs. "Meaning" here refers to whatever should be represented by a good dictionary. For instance, the word "bank" has several distinct lexical definitions, including "
financial institution" and "
edge of a river". Or consider "
apothecary". One could say, "I bought herbs from the apothecary". This could mean one actually spoke to the apothecary (
pharmacist) or went to the apothecary (
pharmacy). The context in which an ambiguous word is used often makes it clearer which of the meanings is intended. If, for instance, someone says, "I put $100 in the bank", most people would not think someone used a shovel to dig in the mud. However, some linguistic contexts do not provide sufficient information to make a used word clearer. Lexical ambiguity can be addressed by
algorithmic methods that automatically associate the appropriate meaning with a word in context, a task referred to as
word-sense disambiguation. The use of multi-defined words requires the author or speaker to clarify their context and sometimes elaborate on their specific intended meaning (in which case, a less ambiguous term should have been used). The goal of clear, concise communication is that the receiver(s) have no misunderstanding about what was meant to be conveyed. An exception to this could include a politician whose "
weasel words" and
obfuscation are necessary to gain support from multiple
constituents with
mutually exclusive conflicting desires from their candidate of choice. Ambiguity is a powerful tool of
political science. More problematic are words whose multiple meanings express closely related concepts. "Good", for example, can mean "useful" or "functional" (''That's a good hammer
), "exemplary" (She's a good student
), "pleasing" (This is good soup
), "moral" (a good person
versus the lesson to be learned from a story''), "
righteous", etc. "I have a good daughter" is not clear about which sense is intended. The various ways to apply
prefixes and
suffixes can also create ambiguity ("unlockable" can mean "capable of being opened" or "impossible to lock").
Semantic and syntactic ambiguity Semantic ambiguity occurs when a word, phrase, or sentence has more than one possible interpretation. For example, in the sentence "We saw her duck", the phrase "her duck" is ambiguous and can mean: • the woman’s bird (
noun phrase where the noun
duck is modified by the possessive pronoun
her), or • an action the woman performed (
verb phrase with
duck as a verb and
her as the
object of
saw). For syntactic ambiguity in
formal languages (such as computer
programming languages), see
ambiguous grammar. Conversely, a sentence like "He ate the cookies on the couch" is also semantically ambiguous. Rarely, but occasionally, the different parsings of a syntactically ambiguous phrase result in the same meaning. For example, the command "Cook, cook!" can be parsed as "Cook (
noun of address), cook (imperative verb form)!", but also as "Cook (imperative verb form), cook (noun of address)!" It is more common that a syntactically unambiguous phrase has a semantic ambiguity; for example, the lexical ambiguity in "Your boss is a funny man" is purely semantic, leading to the response "Funny ha-ha or funny peculiar?"
Spoken language can contain many more types of ambiguities that are called phonological ambiguities, where there is more than one way to compose a set of sounds into words, such as "ice cream" and "I scream". Such ambiguity is generally resolved according to the context. A mishearing of such, based on incorrectly resolved ambiguity, is called a
mondegreen. == Philosophy ==