Indefinite Article

The term indefinite article is misleading. Many assume that it refers to nothing in particular. However, this is seldom the case.

Consider the sentence There is a spider in the bathroom. In this case, the speaker is referring to a very specific insect. In the sentence I know a lady who always wears colourful hats, the speaker is referring to a particular woman with a particular taste in clothes.

In certain cases, however, the indefinite article does not have a specific reference. This is the case with the sentence I want a good job. The grammatical context reveals if the reference is specific or not.

The following sentences on the left have a specific reference, but the ones on the right do not:

Kevin is dating a nice woman. Kevin is looking for a nice woman.
She is slicing a juicy pineapple. I enjoy a juicy pineapple.
I see a red Ferrari. I want a red Ferrari.
I witnessed a bad accident. I fear a bad accident.

The sentence I am looking for a tie is potentially ambiguous. If the speaker continues with I've found it, the noun phrase a tie has a specific reference. However, if the speaker continues with I found one, the noun phrase has no specific reference.

Despite its name, the indefinite article often has a specific reference. The grammatical context makes it clear whether the reference is specific or not. The definite article is thus not the only one with a specific reference.