Get it right people!

Over the past few months I've noticed more and more instances of people confusing the words 'then' and 'than'. Even though they are almost homophones¹ it's not that hard to tell the difference, one has an 'a' where the other has an 'e', but I'm guessing the real problem is not knowing their definitions and usage properly.

Then

Then has a variety of meanings and is used primarily as an adverb but can also be used as a noun. An adverb is a word used to alter the meaning of another word or phrase (either a verb, adjective, adverb or prepositional phrase) and there are a variety of ways then can be used as an adverb.

1. to indicate a certain time (The parties were wild back then.)
2. next in order; soon afterward (I drank the whole bottle, then didn't feel very well. The order of the first four planets is Mercury, Venus, Earth then Mars.)
3. in addition to (My dislocated shoulder was really hurting, then the pain doubled when the doctor yanked it back into place.)
4. in that case (If the phone rings then answer it.)
5. on the other hand (She has sw'as features, but then, she is only a line drawing)

As a noun, then has only limited use². Primarily it's used to refer to a specific time. Before then, there's no point trying.

Than

Than is primarily used as a conjunction³ and sometimes as a preposition⁴. As a conjunction it is typically used together with an adjective as a way of comparing two things. e.g. I am taller than you are. The mood in here is much different than the mood outside.

Somewhat confusingly⁵ than can also be used (as a conjunction) in much the same situation as then might be used to indicate a point in time, with the resultant meaning of the sentence being different in a subtle way. Consider the following two sentences.

• I had scarcely taken my first sip than the wine went to my head.
• I had just taken my first sip, then the wine went to my head.

The first of the sentences uses than in a very specific way which (as far as I know) always involves one of the words scarcely or hardly. To make the second sentence a little bit nicer I have also changed scarcely to just but that need not have been done. The second sentence uses then as in definition/example two above.

As well as being used as a conjunction, than can be used as a preposition. Although its usage as a preposition is wide spread, especially in speech, many hard core grammartarians still regard the use of than this way as incorrect⁶

Although I like correcting people, I also regularly get things wrong. So, if that's the case here please let me know.

1. They are pronounced in the same way but are spelt differently and have different meanings. [↩]
2. It's sometimes very difficult to tell the difference between then as a noun and then as an adverb [↩]
3. Simply a word used to join two parts of a sentence together. The specific conjunction used dictates how the parts of the sentence are related. [↩]
4. I don't completely understand prepositions but one of the ways they are used is to modify, limit or qualify some other word, usually a noun or pronoun. e.g. I corrected my mistake with White-Out. Here the preposition with is used with the proper noun White-Out to form a prepositional phrase that modifies or qualifies the verb phrase I corrected my mistake. [↩]
5. But it's these kinds of subtle differences that make the English language so great. [↩]
6. For a good write up on this see the section on than here or the Answers.com definition usage note. [↩]