First of all some remarks on the terminology used.
Adverb (副詞) is the usual definition as it can be found in dictionaries. The other two words require some more thought.
It seems 時相名詞 is a technical term used by jumandic, a dictionary for morphological parsers. Here's the only insight I could find:
Thus: temporal noun = a noun that can be used adverbially. You can use a word such as 今年 like a noun or adverbially:
Often these are nouns related to time (hence the name), but not necessarily. 全部 is classified as a temporal noun as well. However, I would judge this to be a classification error, considering the name and that most of them are indeed related to time.
Furthermore, this classification might be necessary in the context of parsing Japanese, but I suppose it is probably irrelevant if you only want to learn the language. Also, the paper I linked mentions that this classification might not be the best.
Next, 副詞的名詞 is used by jumandic too. It's also used on the net and in papers in the context of Japanese and other languages. In ipadic this is called 副詞可能. It refers to nouns (or words originating from a noun) that can be used adverbially such as ところ, ため, ぐらい. For example:
(from the noun 位【くらい】, from 座【くら】居【い】る)
In this paper there is a remark on adverbial nouns:
This seems to suggest that an adverbial noun must admit the possibility to accept modifiers (adjectives, relative clauses &c.), such as in the above example or this:
- 肝炎ウイルスは多くの場合、 感染しても自覚症状が無く本人が気がつかない。
Are all temporal nouns also adverbial nouns?
First of all, it should be obvious that not all adverbial nouns are temporal. As for the other direction, most temporal nouns appear to be adverbial nouns too, namely 445/592(75%) of them. Those that are alo adverbial can be modified:
However, here are some words marked only as
temporal noun in jmdict:
Referring to the definitions given above, here the explanation for this would seem to be that while 今日【きょう】 or これから can be used adverbially in a sentence, you cannot modify it usually.
On the other hand, 昨日【きのう】 is marked as both temporal and adverbial noun in edict/jmdict. If we look it up directly in jumandic, we find:
Thus my conclusion is that the tagging of 昨日【きのう】 is a mistake in edict/jmdict.
Is it true that adverbs can't be the topic of a Japanese sentence; but adverbial nouns and temporal nouns can be?
I'm going to assume that by
can be the topic you mean
can be marked with the focus/topic particle は. Also, any word can be used with は when making a comment about that word in the form
「甲」は乙 (mentioning rather than using it, eg. 恰【あたか】もはかたい表現), so I will exclude this usage from the following discussion.
First temporal and adverbial nouns. This is easily answered by providing some examples. Many words can be topicalized:
- 毎月第2火曜日temporal, adverbialは庁舎周辺のごみ拾いをしましょう。
- 3月10日未明temporal, adverbialは敗戦の序章・東京大空襲の日
Now let us turn to adverbs. Some words marked as adverb in edict/jmdict include:
Some of these are not only marked as adverb, but also as (na/no-)adjective &c., which might explain why they can be used with the focus particle は. For example:
So let us consider a word marked as adverb only: いくつ, たびたび, とても, and もし.
It's true that usually you wouldn't use them as the topic of the sentence or with the particle は. However, language is flexible and people use it to fit their needs. Often, whether something is possible or not is only a function of how hard you're looking. Consider the following sentences:
from 徳田秋声全集 第三期 長篇小説, ISBN 4-8406-9693-4
This is the best I can come up with.
But it's borderline mentioning the word.
(from 全国ご古語辞典 第三版 旺文社 2003)
In edict/jmdict, these words are marked only as
adverb. I'll leave it to you to decide whether they are adverbs in the above sentences. The point is, some of them can be used with は.
Other adverbs such as のんびり or あたかも are extremely rare with the particle は, so we can't make a general statement that they could or couldn't be used with は.
- most temporal nouns are adverbial nouns
- some adverbs can be used with the particle は, but it depends upon the word and isn't too common
- these classifications are not important unless you're a linguist or programmer