fun

[Lenka]

I read the following sentence somewhere:

It was a fun but hard project.

I don't understand, why the indefinite article "a" was used there! The noun "fun" is uncountable, isn't it?

[Casiopea]

Try looking at it this way, Lenka,

EX: It was a fun [project], but a hard project.

The first noun, [project], has been omitted for the sake of efficiency.

All the best.

[Lenka]

Try looking at it this way, Lenka,

EX: It was a fun [project], but a hard project.

The first noun, [project], has been omitted for the sake of efficiency.

All the best.

Why is "fun" used instead of "funny", then? Word "fun" isn't an adjective, is it?

[Philly]

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Yes, fun is used as an adjective meaning enjoyable. The usage would typically be informal, but you should be able to find fun defined in any good dictionary also as an adjective. ;)
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Funny can mean comical (causing laughter) or strange.
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