Alongside the productive, everywhere-applicable 〜さ nominalizer, Japanese has a second, quieter suffix that also turns adjectives into nouns: 〜み. 痛い ("painful") gives 痛み ("pain"); 深い ("deep") gives 深み ("depth" in the sense of richness); 重い ("heavy") gives 重み ("weight" in the sense of gravity or significance). But 〜み is a very different animal from 〜さ. Where 〜さ measures a quality on a scale, 〜み names the quality as something felt, experienced, or concretely present — and, crucially, 〜み only attaches to a fixed, smallish set of adjectives. You cannot form it freely.
This page teaches which words take 〜み, what it means, and — the part learners most need — exactly where the み/さ line falls, because English collapses both into words like depth, warmth, and weight, and getting the wrong one sounds distinctly off.
What 〜み does: names a felt or concrete quality
The best single gloss for 〜み is "the X-ness you can perceive, feel, or point to." 甘み is not "how sweet on a scale" but "the sweetness you taste"; 温かみ is not "temperature in degrees" but "a felt warmth of character"; 深み is not "how many meters deep" but "a felt richness." The suffix makes the quality into something almost tangible — a substance rather than a measurement.
| Adjective | Noun | Meaning |
|---|---|---|
| 痛い (itai) | 痛み (itami) | pain (a felt sensation) |
| 楽しい (tanoshii) | 楽しみ (tanoshimi) | a pleasure / something to look forward to |
| 深い (fukai) | 深み (fukami) | depth, richness, profundity |
| 重い (omoi) | 重み (omomi) | weight in the sense of gravity / significance |
| 温かい (atatakai) | 温かみ (atatakami) | warmth of feeling |
| 甘い (amai) | 甘み (amami) | sweetness (as tasted) |
| 強い (tsuyoi) | 強み (tsuyomi) | a strong point / advantage |
| 弱い (yowai) | 弱み (yowami) | a weak point / vulnerability |
傷の痛みがなかなか引かなくて、病院に行った。
kizu no itami ga nakanaka hikanakute, byōin ni itta
The pain from the cut just wouldn't fade, so I went to the hospital.
このワインは深みがあって、香りも豊かだ。
kono wain wa fukami ga atte, kaori mo yutaka da
This wine has depth, and the aroma is rich too.
経験者の言葉には、やっぱり重みがある。
keikensha no kotoba ni wa, yappari omomi ga aru
The words of someone with real experience carry weight after all.
楽しみ: the star example with no 〜さ twin
The clearest proof that 〜み is doing something 〜さ cannot is 楽しみ. Both 楽しさ and 楽しみ exist, but they mean genuinely different things:
- 楽しさ (〜さ) = "funness," the degree to which something is fun. 旅行の楽しさ = "how enjoyable the trip is."
- 楽しみ (〜み) = "a pleasure / a thing to look forward to." 旅行が楽しみ = "I'm looking forward to the trip."
There is no way to get 楽しみ's forward-looking "anticipated pleasure" meaning out of 楽しさ. This is the single best pair to lock in, because it shows that 〜み is not just "a fancier 〜さ" — it opens a meaning the measuring suffix simply does not have.
久しぶりに家族に会えるので、週末が楽しみです。
hisashiburi ni kazoku ni aeru node, shūmatsu ga tanoshimi desu
I get to see my family for the first time in a while, so I'm looking forward to the weekend.
新しいカフェができたんだって。行くのが楽しみ！
atarashii kafe ga dekita n datte. iku no ga tanoshimi
I hear a new café opened. I can't wait to go!
The heart of the matter: 〜み vs 〜さ
Line up the same adjective under both suffixes and the division of labour is sharp. 〜さ gives you the measurable amount; 〜み gives you the felt quality or a concrete manifestation of it.
| Adjective | 〜さ (measured quantity) | 〜み (felt / concrete quality) |
|---|---|---|
| 深い | 深さ = depth as a measurement (プールの深さ, "the pool's depth") | 深み = richness, profundity (味に深みがある, "the flavor has depth") |
| 重い | 重さ = weight in kilograms (荷物の重さ, "the luggage's weight") | 重み = gravity, significance (一言の重み, "the weight of a single word") |
| 甘い | 甘さ = degree of sweetness (甘さ控えめ, "lightly sweetened") | 甘み = the sweetness you taste (トマトの甘み, "the tomato's sweetness") |
このトマト、驚くほど甘みがあるね。
kono tomato, odoroku hodo amami ga aru ne
This tomato is surprisingly sweet, isn't it.
手書きの手紙には、メールにはない温かみがある。
tegaki no tegami ni wa, mēru ni wa nai atatakami ga aru
A handwritten letter has a warmth that email doesn't.
Why you cannot form 〜み freely — and 高み as the cautionary tale
The trap for English speakers is to treat 〜み like 〜さ and slap it on any adjective. It does not work: 〜み is semi-lexicalized, meaning each 〜み word is more like an established vocabulary item than a form you generate on demand. Most adjectives simply have no 〜み form at all — 長み, 速み, 大きみ are not words.
The sharpest illustration is 高い. Its measuring noun is 高さ ("height"). The form 高み does exist — but it does not mean "height as a measurement." It means "a lofty height / an elevated vantage," as in the idiom 高みの見物 ("watching from a safe, detached perch"). So if you want to say a building's height, 高み is flatly wrong; you need 高さ. The very existence of 高み with a different meaning is the perfect warning: 〜み is not a productive measuring suffix, and each form carries its own settled sense.
彼らはただ高みの見物を決め込んでいた。
karera wa tada takami no kenbutsu o kimekonde ita
They just settled in to watch from the sidelines, uninvolved.
A native-speaker note: 〜み is coming back (slang)
Here is something even textbooks miss. In recent internet and youth speech (slang), 〜み has become productive again, coined freely on adjectives and even nouns to name a mood or vibe: つらみ ("the feeling of it being rough," from 辛い), わかりみ ("that feeling of totally getting it," from 分かる), しんどみ ("a sense of being worn out"). These are (informal, youth slang) and would be out of place in an essay or a business email, but you will see them constantly online. They are worth recognizing — and they cleverly exploit exactly the "felt quality" core of 〜み described above.
この曲、エモくて優勝。わかりみが深い。
kono kyoku, emokute yūshō. wakarimi ga fukai
This song is so moving, it wins everything. I feel it so deeply. (youth slang)
How this differs from English
English uses one set of nouns — depth, warmth, weight, sweetness — for both the measurable and the felt sense. "The depth of the pool" and "the depth of her character" are the same word depth; only context tells them apart. Japanese splits them lexically: 深さ for the pool, 深み for the character. So translating an English -th or -ness noun into Japanese forces a decision English never made you make: which depth do you mean, the metered one or the felt one? Reading "the weight of his words," an English speaker feels no pull toward a suffix, but the Japanese writer must choose 重み (gravity), not 重さ (kilograms) — and choosing 重さ there would sound like you were literally weighing his words on a scale.
The second difference is productivity, already stressed: English -ness attaches quite freely, so learners expect a Japanese equivalent to as well. 〜さ meets that expectation; 〜み does not. Treat 〜み words as vocabulary to be learned one by one, not as a rule to apply.
Common Mistakes
1. Forming 〜み freely on any adjective. It attaches only to a fixed set; most adjectives have no 〜み form.
❌ この橋の長みはどのくらい？
kono hashi no nagami wa dono kurai
Incorrect — 長み is not a word; for length use 長さ.
✅ この橋の長さはどのくらい？
kono hashi no nagasa wa dono kurai
How long is this bridge?
2. Using 〜み where a measurement is meant. For a number-bearing quantity, use 〜さ.
❌ 荷物の重みは三キロです。
nimotsu no omomi wa san kiro desu
Incorrect — for a measured weight use 重さ; 重み is gravity/significance.
✅ 荷物の重さは三キロです。
nimotsu no omosa wa san kiro desu
The luggage weighs three kilos.
3. Substituting 楽しさ for 楽しみ (or vice versa). "Looking forward to" is 楽しみ; the degree of fun is 楽しさ.
❌ 明日の遠足がとても楽しさです。
ashita no ensoku ga totemo tanoshisa desu
Incorrect — for 'looking forward to' use 楽しみ, not 楽しさ.
✅ 明日の遠足がとても楽しみです。
ashita no ensoku ga totemo tanoshimi desu
I'm really looking forward to tomorrow's outing.
4. Forgetting to drop the final い. As with 〜さ, you replace 〜い with み.
❌ 傷の痛いみがひどい。
kizu no itai-mi ga hidoi
Incorrect — drop the final い: 痛い → 痛み.
✅ 傷の痛みがひどい。
kizu no itami ga hidoi
The pain from the wound is terrible.
Key Takeaways
- 〜み turns a limited, fixed set of adjectives into nouns naming a felt quality or concrete instance: 痛み, 深み, 重み, 温かみ, 甘み, 強み/弱み.
- It is not productive — learn each 〜み word as vocabulary. Most adjectives have no 〜み form; the safe default is 〜さ.
- み vs さ: 〜さ = the measurable amount (深さ = meters); 〜み = the felt/concrete quality (深み = richness). English uses one word for both.
- 楽しみ ("anticipated pleasure") has no equivalent 楽しさ meaning — proof that 〜み opens senses 〜さ cannot.
- 高み exists but means "a lofty vantage," not "height as a measure" — a warning that each 〜み form has its own settled meaning.
- 〜み has revived as (youth slang): つらみ, わかりみ — recognizable online, out of place in formal writing.
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