"than" can be used as a conjunction and as a preposition. I want to be able to tell for any given sentence containing "than" which grammatical function it has in that sentence.

My current understanding is as follows:

  1. When "than" connects two clauses or phrases it's a conjunction. Examples: We shouldn't spend more than we earn. He's taller than I am.
  2. This also applies when the second clause or phrase is elliptical: He's taller than I.
  3. But when "than" occurs with a pronoun in the objective case, it's a preposition: He's taller than me.
  4. It's also a preposition when numbers/amounts are compared: It takes less than an hour. A crowd of more than 10,000 had gathered.

Is this correct so far?

I'm confused about the following:

But aren't these all elliptical sentences (e.g. I'm taller than my dad is), and hence all cases of "than" as conjunction?

My question has a practical background: I want to apply proper title case to a number of song titles. According to both the Chicago Manual of Style and the Wikipedia Manual of Style, four-letter prepositions are not capitalized while (subordinating) conjunctions are capitalized, so I need to be able to make the distinction.

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    Collins attempts to deal with the acceptable usages and corresponding allocation of word classes involved with than by labelling it 'conj, prep (coordinating)' for all usages. I don't know whether this means they subscribe to the gradience (somewhere between conjunction and prepopsition) or the hybrid (both conj and prep at once) interpretation. Perhaps you could capitalise at weekends. Or ask the people at CMS etc. Or use a different style guide. Feb 25, 2015 at 18:05
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    This is a controversy that’s been hotly debated since the eighteenth century. Grammar Girl ends up endorsing Than is both a subordinating conjunction, as in "She is wiser than I am", and a preposition, as in "She is wiser than me". Feb 25, 2015 at 18:09
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    As "than" can only occur after a comparative I wouldn't care about what dictionaries or grammars say, the meaning of comparative + than is always the same. It would be simpler to label "than" as function word after comparative. - You see that dictionaries have diverging views and how arbitrary those labels are. With some function words it is no great use asking what word class they are. It isn't important because the only have one single use.
    – rogermue
    Feb 25, 2015 at 18:10
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    Please could one of you explain to me why Americans say different than? For me it is always different to. John is different to me. When did our colonial cousins start saying than? Is this one of the things we blame (as someone did with something the other day) on the 132 people who sailed in the Mayflower? Did they start it all?
    – WS2
    Feb 25, 2015 at 18:59
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    @WS2, some of us even say and prefer different from. Feb 25, 2015 at 19:43

2 Answers 2


"Than" is neither a conjunction nor a preposition, it is a special function word with only one single use - after a comparative. Actually it can only be used in the structure verb (mostly to be) + comparative + than + complement. Prepositions or conjunctions don't behave in this way.

Dictionaries that label this function word as conjunction or preposition have no feeling that this special word does not fit into these two word classes.

Even etymonline uses the label conjunction. And its historical explanation does not help much.

I can give only my view: If you say Peter is taller than his sister, you say: Peter is taller (seen from there: seen from his sister). In German there is the word davon (there+from). This could give an understanding of the word than. In German there is also an old "denn" after comparative:

Geben ist seeliger denn Nehmen (Giving is better than taking). And we have an old "von dannen" (from there).

If you talk about the size of a thing A, you can compare it with a thing B. And you can say compared with B A is taller - or you can say: seen from B A is taller.

This way of expressing the idea was already in use in Latin. The Romans used an ablative (indicating from where) after a comparative: Nulla bestia fidelior est cane (No animal is more loyal than the dog). You could explain: "No animal is more loyal (seen) from the dog." This ablative is called ablativus comparationis (ablative of comparison).

So "than" has a special origin and exactly one use comparable to the function word "ago" and you get problems if you want to force such a word into the traditional word classes. That does not help to understand the word, on the contrary. You get wrong ideas. And some begin to rack their brain when "than" is a conjunction and when a preposition.

  • Okay, neither preposition nor conjunction... but then, should one use "better than he" or "better than him"? Perhaps both are good? Mar 10, 2016 at 17:13
  • @laugh - It depends on whether you're talking about prescriptive or descriptive grammar. Prescriptively (meaning, here's how we should speak, according to some experts), "than he" is correct and "than him" is incorrect. Descriptively (meaning, this is how people actually use English), "than him" is more common, but I have no idea how experts would justify it, since a comparative requires (prescriptively!) both sides to be of the same type. Dec 1, 2017 at 18:49

Constituents of the same grammatical category can be coordinated by "and":

NP: [George] and [the young seals]
VP: [gleams] and [reflects in blue]
PP: [in Georgia] and [over the Atlantic]
P: [over] and [under] the table

But constituents of different categories cannot:

*[George] and [under]
*[reflects in blue] and [George]

Are "than" phrases and PPs of the same category?

*Tartar sauce is better [on fish] and [than ketchup].
*I like oysters more [than oatmeal] and [on the half-shell].


Is "than" a preposition?

*He ate more [than] and [beside] the eagle.


Rather than collecting opinions from here and there on whether "than" is a preposition, wouldn't it be better to find evidence from English?

  • How about the test 'doesn't take an independent clause as a complement' for prepositions? *'I gave the book to John is reading.' 'He has eaten more trifle than John [has eaten].' Jul 12, 2023 at 16:42

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