Is the phrase 'tiny bit' an idiom or an adverb and a noun?

I have found in WordReference English-Greek Dictionary that the phrase 'tiny bit' is an adverb and a noun. That dictionary gives the following examples:

1. This version is just that tiny bit better than the first, but you still need to revise it.
2. I was a tiny bit sad to say goodbye to my friends, but excited about the adventure I was embarking upon.
3. There's a tiny bit of milk left in the bottle.
4. That tiny bit of cake will never satisfy Tania's appetite.

In the first and the second examples the phrase 'tiny bit' is an adverb and in the third and the fourth examples the phrase 'tiny bit' is a noun.

I know from school that 'tiny bit' means 'a little bit'. I have found in Longman Dictionary that the phrase 'a little bit' is an idiom.

Can I say that the phrase 'tiny bit' is an idiom? WordReference English-Greek Dictionary says that the phrase 'tiny bit' is an adverb and a noun. Is that correct? Is the phrase 'tiny bit' an idiom or an adverb and a noun?

Solution 1:

Yes, there are different usages here.

'... a tiny bit sad ...' and 'that tiny bit better' (compare 'somewhat') show adjective-premodification (here, downtoning: contrast intensifying, with 'very/extremely'; 'much'), and are still labelled in this role as (compound, ie multi-word) 'adverbs' by some traditionalists. I'd go with the 'splitting rather than lumping' analysis explained by Hurford James R in 'Grammar: A Student's Guide' (p9) here:

Some words, such as very, quite, rather, and somewhat, which modify adjectives and adverbs, are sometimes [themselves also] called adverbs, but that is not a very good name for these, because all sorts of other words are also called adverbs, and the term begins to get vague and unspecific. (Actually, linguists use the term[] ... degree modifier [secondary modifier; intensifier / downtoner] for very, quite, rather, and somewhat [and awfully, alarmingly, incredibly, seriously ... when used to modify adjectives/adverbs].

The term 'degree modifier' is well known, but 'secondary modifier (of adjective, etc)' is more fitting for the whole class, as 'alarmingly', 'strappingly', 'calculatedly ... carry semantic weight far beyond the mere intensification / downtoning words live 'very', 'slightly' carry.

'Slightly sad' / 'a bit sad' show downtoner usage; 'a tiny bit sad' shows a mitigated downtoner (second order, with the downtoner itself being downtoned!) usage.

On an even keel, a tiny bit sad, a bit sad, rather sad, sad, very sad, worryingly sad, extremely sad....

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'[A] tiny bit of' is a [compound] [intensified; the archetypal compound quantifier is 'a bit of'. Note that here, 'tiny' reinforces 'bit' (downwards!), rather than mitigating an adjective as in 'a tiny bit better'] quantifier.

As explained in an article on Grammar put out by the British Council:

Quantifiers with uncount nouns

Some quantifiers can be used only with uncount nouns:

(not) much // a bit of // a little

Would you like a little wine?

Could I have a bit of butter, please?

.........................

I've avoided the word 'idiom', as premodification of adjectives is totally standard grammar, however it is analysed. No words are used with unusual senses either (as @Jason Bassford et al points out), so 'idiom' is not applicable (and I'd use 'compound premodifier' and 'compound quantifier' rather than 'fixed expression' here myself). But I understand why you're asking about the wisdom of treating say 'a bit of' as a single lexeme. Analysis into say [indefinite article] + [noun] + [preposition] doesn't get us very far, when 'a little' and 'a bit of' are largely interchangeable.