It contrasts with kyōjaku akusento (強弱アクセント, literally "strong-and-weak accent"),[1] which refers to stress.

The current standards for pitch accent are presented in special accent dictionaries for native speakers such as the Shin Meikai Nihongo Akusento Jiten (新明解日本語アクセント辞典) and the NHK Nihongo Hatsuon Akusento Jiten (NHK日本語発音アクセント辞典).

This, and the initial rise, are part of the prosody of the phrase, not lexical accent, and are larger in scope than the phonological word.

In other words, the precipitous drop in pitch occurs right at the boundary between the accent nucleus and the mora immediately after it.

They historically arose through various processes that limited their occurrences and prominence in terms of accent-carrying capability.

For example, the utterance 母が料理をして父が皿を洗います (Haha-ga ryōri-o shite chichi-ga sara-o arai-masu "My mother cooks and my father washes the dishes") can be subdivided into the following phrases: The general structure of these phrases is that a syntactically free morpheme is followed by one or more syntactically bound morphemes.

In the above utterance, the free morphemes are 母, 料理, して, 父, 皿, and 洗い while the bound ones are が, を and ます.

Thus, the utterance ヨーロッパは第一次世界大戦では主戦場となった (Yōroppa-wa Dai-ichiji-Sekai-Taisen-de-wa shusenjō-to natta "Europe was the main theater of war in World War I") is subdivided into phrases as follows: As Dai-ichiji-Sekai-Taisen-de-wa is an entire phrase in itself, it should ideally carry at most one accent nucleus, the lexical accent nucleus of the free compound noun Dai-ichiji-Sekai-Taisen.

While still being a syntactic compound, its components might not be solidly "fused" together and still retain their own lexical accent nuclei.

A yojijukugo such as 世代交代 (sedai-kōtai "change of generation") may be treated as "compoundified," with a single accent nucleus:[6] Meanwhile, a different four-kanji compound noun, 新旧交代 (shinkyū-kōtai "transition between the old and the new"),[6] is treated as "noncompoundified", and retains the lexical accent nuclei of its constituents (in this case 新旧 and 交代): Some compound nouns, such as 核廃棄物 (kaku-haikibutsu "nuclear waste"), can be, on a preferential basis, either "compoundified" or "noncompoundified": For "noncompoundified" compound nouns, which constituents should be allowed for may also vary.

Different analyses may treat final-accented (odaka) words and unaccented (heiban) words as identical and only distinguishable by a following particle, or phonetically contrastive and potentially phonemic based on how high a "high" tone actually is (see the Tertiary pitch subsection below).

Most of the following patterns are listed in the NHK日本語発音アクセント辞典 (NHK Nihongo Hatsuon Akusento Jiten, lit.

'NHK Japanese Pronunciation & Accent Dictionary') and the 新明解日本語アクセント辞典 (Shin Meikai Nihongo Akusento Jiten, lit.

According to the appendix アクセント to the Daijirin, here are the patterns for the 連用形 of monograde verbs without a trailing particle or auxiliary: The derived noun from くらべる is くらべ (accentless).

Certain highly productive affixes, often of Sino-Japanese origin, often result in compound nouns with predictable accent patterns.

are attributively modified by another accentless or odaka word and simultaneously followed by a particle or an auxiliary, the accent of the entire phrase may fall on the last mora of such nouns.

The -ku 連用形 of accentless adjectives are also accentless: The accent nucleus of the -ku 連用形 of accented adjectives is shifted one mora backward if posssible; OR, if the -ku form contains more than 3 morae, is the same as that of the dictionary form: Group V consists of the following particles: て、は、も、ても.

The following list for Tokyo accent is not shown in the NHK日本語発音アクセント辞典, but slightly reworked from papers by Shiro Kori.

[3] The following chart gives some examples of minimal pairs of Japanese words whose only differentiating feature is pitch accent.

With the simple addition of the particle ni "at", for example, /hasiꜜni/ hàshí-nì "at the bridge" acquires a marked drop in pitch, while /hasini/ hàshi-ni "at the edge" does not.

[16] This property of the Japanese language allows for a certain type of pun, called dajare (駄洒落, だじゃれ), combining two words with the same or very similar sounds but different pitch accents and thus meanings.

In the neighboring areas of Tokyo-type and Keihan-type such as parts of Kyushu, northeastern Kanto, southern Tohoku, around Fukui, around Ōzu in Ehime and elsewhere, nouns are not accented at all.

In western and southern Kyushu dialects (pink area on the map on the right), a high tone falls on a predictable syllable, depending only on whether the noun has an accent.

For instance, in the Kagoshima dialect unaccented nouns have a low tone until the final syllable, at which point the pitch rises.

The ultimate or penultimate high tone will shift when any unaccented grammatical particle is added, such as nominative -ga or ablative -kara: In the Shuri dialect of the Okinawan language, unaccented words are high tone; accent takes the form of a downstep after the second syllable, or after the first syllable of a disyllabic noun.

Nikei accents are also found in parts of Fukui and Kaga in Hokuriku region (green area on map).

In Miyakonojō, Miyazaki (small black area on map), there is a single accent: all phonological words have a low tone until the final syllable, at which point the pitch rises.

Near the old capital of Kyoto, in Kansai, Shikoku, and parts of Hokuriku (the easternmost Western Japanese dialects), there is a more innovative system, structurally similar to a combination of these patterns.

Unaccented low-tone words such as usagi 'rabbit' have high pitch only in the final mora, just as in Kagoshima: Hokuriku dialect in Suzu is similar, but unaccented low-tone words are purely low, without the rise at the end: sakura has the same pattern as in Osaka.

That is, a stressed syllable in Tokyo dialect, as in 貝 kai 'shell' or 算 san 'divining rod', will always have the pattern /kaꜜi/ [káì], /saꜜɴ/ [sáɴ̀], never */kaiꜜ/, */saɴꜜ/.