What is an adnominal adjective is? The word "adnominal" simply means something that modifies a noun. In which case, all adjectives are adnominal. However, adnominal adjectives in the realm of Japanese grammar refer to adjectival phrases that don’t conjugate and solely modify the noun they attach to and are not interpreted as predicates modifying a noun (participle).
Adnominal adjectives (Rentaishi 連体詞) are easily distinguished from normal adjectives by the fact that they are all variants of normal adjectives. Appearance-wise, adnominal adjectives all end in /na/ whereas their normal variants all end in /i/. For instance, let's look at chiisai 小さい and chiisana 小さな, which both translate as "small" but behave differently syntactically following the basic principle mentioned above.
Yama no chiisai toritachi wo kanshō shite imasu.
I’m admiring the small birds of the mountain.
Ano yama no chiisana machi ni sunde imasu.
I live in the small town on that mountain.
Nihonjin wa hontō ni taikaku [ga/no] chiisai jinshu na n desu ka?
Are Japanese really a race whose build is small?
Particle Note: Either ga が or no の can be used to mark what would be the subject if the dependent clause were being used as an independent clause.
Of the two forms, only chiisai 小さい can be seen at the end of a sentence, which is why you can view it as the "predicate form". Naturally, predicates tend to be full phrases, and these full phrases can then in turn be embedded into a noun phrase as one big modifier, which we call a participle.
As is the case with English, though, noun phrases can be modified by more than one phrase simultaneously. This would seem to be the case in i., but in this example it would be incorrect to view 小さい acting as a predicate embedded into a noun phrase. It is simply being used to mean "small bird". This prevents the speaker from interpreting 山の小さい鳥たち as "birds with small mountains", which would be nonsensical.
What this means is that 小さい and 小さな do coincide a lot. Syntactically, they're identical in i. and ii., with iii. being the example in which 小さい is indeed part of a complex participle embedded into a noun phrase, which is a function that 小さな cannot have. It is this syntactic complexity that tells the reader the phrase 小さい is a part of must be treated as a participle.
Adnominal adjectives in many ways are just like no-adjectives or any other modifying phrase that utilizes the particle no の. The only difference is that adnominal adjectives must be directly attached to the noun they modify whereas phrases with no の like yama no 山の in i. can float, meaning they are not bound directly before the noun they modify.
Although adnominal phrases do not inherently have the syntactic role of behaving as predicates, there are rare instances of this being broken when the otherwise participle is only composed of the adjective itself due to abnominal adjectives being more common before nouns than their non-abnominal forms.
[Chiisai/chiisana] toki kara daisuki deshita.
I loved it since I was little.
As to be expected, chiisai toki 小さい時 is the default choice to express this. However, it just so happens that chiisana 小さな is statistically used more in front of nouns. This is due to the fact that the two forms create a predicate/non-predicate relationship in which the former is typically seen at the end of sentences whereas the latter is typically seen after nouns. Grammatically, however, the former is most correct.
Terminology Note: Adnominal adjectives are called rentaishi 連体詞 in Japanese.
The syntactic difference outlined above is able to explain the differences between adnominal adjectives and non-adnominal adjectives from a distribution standpoint. What it fails to explain, however, is when their distributions overlap, which is the case when neither are viewed as participles when directly modifying a noun. In this grammatical scenario, we must look how they're pragmatically interpreted. Meaning, the forms produce slightly different nuances.
Before getting into further detail, in the chart below you will find a list of all the essential adnominal adjectives (to the right) along with their non-adnominal variants to the left. The first four examples, however, are examples of normal adjectival nouns who share the same variation between /i/ and /na/ based on the same nuancing principles that are to be explained next that are included in the chart to be as thorough as possible.
|Meaning||Ending in /i/||Ending in /na/|
|Fine/minute|| 細かい |
All of the /na/ forms in the right column are examples of adnominal adjectives. Even if any of these words do have other conjugations, those conjugations would be incredibly limited in scope and would need to be studied separately.
1. か細い声はだんだん大きくなっている。(Use of 大きい)
Kabosoi koe wa dandan ōkiku natte iru.
The fragile voice is becoming gradually larger.
2. 驚くほど小さな素足が露になった。 (Use of 小さな)
Odoroku hodo chiisana suashi ga arawa ni natta.
Surprisingly small bare feet became exposed.
Grammar Note: This is an example of 小さな being used as a predicate; however, it is still juxtaposed right before the noun it modifies. Only the degree of the sense of "small" is being modified, and that is via the adverbial phrase 驚くほど. Otherwise, adnominal adjectives do not have the same free range as other adjectives to be used in complex predicate phrases that modify nouns.
3. 小さな声で話しかける。(Use of 小さな)
Chiisana koe de hanashikakeru.
To talk to someone in a small voice.
4. 柔らかかった。暖かかった。(Use of 柔らかい & 暖かい)
It was soft. It was warm.
5. 皮を剥いて細かく切りました。(Use of 細かい)
Kawa wo muite komakaku kirimashita.
I peeled the skin and finely cut it up.
6. 大きい希望の雲が湧いている。(Use of 大きい)
Ōkii kibō no kumo ga waite iru.
Large clouds of hope are gushing forth.
7. 大きな希望の雲が湧いている。(Use of 大きな)
Ōkina kibō no kumo ga waite iru.
Clouds of great hope are gushing forth.
When /i/ and /na/ pairs exist, the ones that end in /i/ are naturally objective, typically used with concrete nouns, but are not limited to literal interpretations, and the ones that end in /na/ are naturally subjective, typically used with abstract nouns, and almost always limited to literal yet emotional interpretations.
However, this is not all you have to consider. Some forms do have nuances the others don’t. You also can’t just choose which form you want in a set phrase. After all, set phrases are set for a reason. With that being said, we will now focus on what exactly these nuance restrictions are.
Chiisai/Chiisana 小さい・小さな Ōkii/Ōkina 大きい・大きな
Generally speaking, chiisana 小さな and ōkina 大きな are only used to indicate physical size but with a subjective twist. Only chiisai 小さい and ōkii 大きい may be used to indicate small/large monetary values, and they may even be used to mean “old” and “young” in the context of age among siblings.
8. ４００円ですか。すみません、｛大きい ○・大きな X｝のしかないんです。
Yonhyakuen desu ka? Sumimasen, [ōkii ○/ōkina X] no shika nai n desu.
It’s 400 yen? I’m sorry, but I only have large ones (bills).
Sekai’ichi chiisai shihei wa nan desu ka?
What is the world’s smallest paper bill?
Ōkiku natta ne.
My, you’ve grown.
Chiisai kara koro zutto sō omotte imashita.
I’ve always thought so since I was little.
Chūō ni chiisana tēburu ga arimashita.
There was a small table in the center.
Sekai de ichiban ōkii tatemono wa nan desu ka?
What is the largest building in the world?
Ōkina seifu wo motomeru hitotachi ga kanarazu doko no kuni ni mo iru.
There are always people who seek big government in any country.
Okashii おかしい vs Okashina おかしな
Okashii おかしい is generally used in positive connotations in the sense of “funny” whereas okashina おかしな is generally used in negative connotations in the sense of “weird/suspicious/odd.” This, of course, is only a rule of thumb, but it generally holds true. However, it is important to note that this distinction really has nothing to do with being objective or subjective or being concrete or abstract.
Okashina kao wo suru.
To make a strange/suspicious face.
Okashii kao wo suru.
To make a strange/funny face.
Okashii hanashi desu ne.
What a strange thing to say.
Okashina kōdō wo toru.
To take strange/suspicious action(s).
Atarashii 新しい vs Aratana 新たな
Although aratana 新たな was grouped as an adnominal adjective above, the adverbial form aratani 新たに does exist, and it is actually quite common. The difference between atarashii 新しい and aratana 新たな is that the former is more suitable for objective/concrete contexts whereas is most suitable for (potentially) subjective/obscure. The latter form also happens to be primarily used in writing and has what can be best described as a ‘cool’ nuance.
That isn’t to say aratana 新たな and aratani 新たに are never used in the spoken language. To the contrary, because they are ‘cool’ sounding with great emotional undertones, they are used extensively in advertisement and the like.
Atarashii kagu wo kaimashita.
I bought new furniture.
Aratana bōken ga hajimaru!
A new adventure will begin!
Atarashii kangae ni tottekawaru.
To replace with a new idea.
Ketsui wo aratani shimashita.
I’ve renewed my resolution.
Yawarakai 柔らかい vs Yawarakana 柔らかな
Yawarakana 柔らかな is only capable of referring to literal softness of the five senses. However, yawarakai 柔らかい may be used more broadly despite being less subjective. For instance, when used in the phrase yawarakai hon 柔らかい本, it can refer to erotica. However, other phrases are more common for this.
As you may have already noticed, whenever forms are not interchangeable, it is the set phrases and obscure instances that only seem to matter. Of course, everything distinguishing /i/ and /na/ forms still apply.
[Yawarakai/yawarakana] kanshoku ni me wo mihiraku.
To open one’s eyes to a tinder sensation.
Yawarakana hizashi wo kanjiru.
To feel gentle sunlight.
Yawarakana monogoshi de sessuru.
To look after/deal with a gentle demeanor.
Yawarakai (o)mochi wo tsukutta.
I made soft rice cake.
Yawarakana (o)mochi wo tabemasen ka?
Why not have some soft rice cake?