Each entry gives the term in traditional and simplified form, its pinyin, the senses it carries in the classical corpus, the passages where it does real work, and how published translations have rendered it.
sān xū
The three emptinesses are the three deficiencies of time. 乘年之衰，逢月之空，失時之和，因爲賊風所傷，是謂三虚 — to ride a year of decline, meet a month whose moon is empty, and lose the harmony of the season, and then be hurt by a thieving wind: that is the three emptinesses. The chapter's claim is that they decide death: 三虚者，其死暴疾也, and that a physician who does not know them 工反爲麤 — turns crude. The set has two uses. In chapter 77 it explains why the same wind kills one man and not another: 三虚相摶，則爲暴病卒死. In chapter 79 it explains why the same wind kills in one year and not the next. Against it stands 三實, the same three in their favour, which the chapter seals in the golden casket.
sān shí
The three fullnesses are the exact reverse of the three emptinesses. 逢年之盛，遇月之滿，得時之和，雖有賊風邪氣，不能危之也 — meet a year at its height, a month at its full, and a season in its harmony, and even thieving wind and evil cannot endanger a man. Huang Di receives the answer with unusual warmth — 善乎哉論！明乎哉道！請藏之金匱，命曰三實 — and then Shao Shi adds the sentence that keeps the doctrine honest: 然此一夫之論也, this is the account of one man. The three are therefore not a promise for a population but a rule for an individual, which is why the chapter can hold both the three emptinesses and the three fullnesses without contradiction.
sān pǐn
The three grades of the pharmacopoeia — upper, middle and lower — and the chapter's one sentence about them: 帝曰：三品何謂？歧伯曰：所以明善惡之殊貫也. The whole weight of the entry lies in the exchange just before it. The emperor has asked about 方制君臣, and the answer has been 主病之謂君，佐君之謂臣，應臣之謂使，非上下三品之謂也 — the lord and ministers of a prescription are not the graded drugs of the materia medica. Pressed on what the grades then are for, the chapter answers with 殊貫: they mark the difference in what each drug is good for and the constancy of it, so that the same drug's rank does not change with the disease while its office in a formula does. The distinction is the chapter's own, and it is why 方制君臣 and 三品 stand apart on this site.
sān bù jiǔ hòu
The diagnostic scheme the chapter is named for. The numbers of heaven and earth begin at one and end at nine: one is heaven, two earth, three the human, and tripling that gives nine, which answers to the nine regions. So the body has three sectors — lower, middle and upper — and each sector has three probes, heaven, earth and human. The nine probes are then matched to named vessels: the upper sector to the arteries at the temples, the cheeks and before the ear; the middle to hand taiyin, hand yangming and hand shaoyin; the lower to foot jueyin, foot shaoyin and foot taiyin. And each probe is given an organ to report on: liver, kidney, spleen and stomach below; lung, chest and heart in the middle; head and temples, mouth and teeth, ears and eyes above. The chapter insists the scheme is not bookish — the probes must be pointed out on a body before they count as true.
sān zàng
The three viscera are the spleen, liver and kidney, and the chapter names them 土木水參居, earth and wood and water dwelling together — a child knows that much, Huang Di says, because they sit side by side below the diaphragm and their pulses therefore come out looking like one another. That is exactly why they matter: 脾虚浮似肺，腎小浮似脾，肝急沈散似腎, and a physician who does not match kinds will read one for another. The chapter's correction comes at the end of the case: 一人之氣，病在一藏也，若言三藏俱行，不在法也 — one man's qi falls ill in one viscus, and to say all three act together is not within the rule.
sān yáng
The three yang are the yang conduits in their three divisions, and the chapter uses the name for their qi rather than for their anatomy: 三陽者，至陽也 — the three yang are the utmost yang. What the chapter then does is follow that one qi through its deviations. It is 天爲業, heaven is its work, so its movement is 上下無常, without constancy above or below; when it arrives alone it is 三陽獨至, and 獨至 is already 并至, a convergence rather than a single current. From that convergence the chapter derives a whole set of signs — 上爲巔疾，下爲漏病, 九竅皆塞, 陽氣滂溢, 乾嗌喉塞, 薄爲腸澼, 三陽直心 — and then closes by turning the same phrase into a question about method: 三陽之病，且以知天下，何以别陰陽，應四時，合之五行. The three yang are thus the chapter's single subject, and every other term in it is a phase of their arriving.
sān yáng zhí xīn
This is the one place in the chapter where a condition is given a name of its own: 此謂三陽直心. It closes a sequence that began with 三陽者，至陽也 and ran through 積并則爲驚, 九竅皆塞, 陽氣滂溢, 乾嗌喉塞, and 薄爲腸澼; after the yang has gathered, blocked the nine openings, overflowed, dried the throat, and pressed into the yin to make dysentery, it goes straight at the heart. The two signs that follow are postural, and they are the reason the phrase is worth an entry: 坐不得起，卧者便身全 — sitting, the patient cannot rise; lying down, the body is at ease. The qi that runs straight at the centre is tolerable only while the body is level. Read with the chapter's own logic, 直 is the key word: the other signs are movements through the conduits, this one is a movement with no conduit at all.
sān yáng tiān wéi yè
The clause stands at the head of the chapter's doctrine and is best read as a definition by office. 三陽天爲業 — the three yang have heaven as their work — and what follows is the consequence: 上下無常，合而病至，偏害陰陽. Because their work is heaven's, their qi has no fixed place above or below; because it has no fixed place, when the currents gather the illness arrives, and it harms yin and yang one-sidedly. 王冰 reads the clause through the old correspondence of father and heaven: the three yang are the greater yang, the greater yang is the father, the father is heaven, and so heaven is its work. The point of the phrase in the chapter is not the correspondence but the mobility — a qi whose office is the whole sky cannot be expected to keep to one region of the body, and the whole doctrine of 獨至 and 并至 follows from exactly that.
yān mén
The first measured gate of the digestive tract. The chapter weighs and measures the gut from the lip to the anus, and this is the segment between the throat and the stomach: ten liang in weight, an inch and a half across, and a foot and six inches long to the stomach. Only the tongue is given a weight besides it, and that is the point — the chapter is measuring a container, not tracing a channel. Later commentators place the gate at the top of the oesophagus and read the weight as the organ's own; the text itself says only where it begins and how far it runs.
jǐn
The tight quality: a pulse drawn taut like a twisted rope, without fixed direction. The book defines it twice over: 脉緊者，如轉索無常也, and by contrast with the string pulse, which is tight but fixed (脉浮而緊者，名曰弦也；弦者，狀如弓弦，按之不移). Tight is the pulse of cold, of the Taiyang stage, and of the three causes the Pingmai fa lists — sweat lost, cold water drunk, diarrhea. It is the quality most characteristic of this book's cold damage.
sān jiāo
Named twice in the Suwen and described the same way both times: it belongs to whatever passes through. In chapter 8 it is the office that opens the channels and from which the waterways emerge; in chapter 11 it is one of the five born of heaven, discharging and not storing. Later writers argued for centuries about whether it has a shape. This chapter takes no position, because it sorts by behaviour and needs only that verdict.
shí èr biàn
The name the chapter gives to its own closing list. Thirteen paragraphs run from 厥陰所至爲和平 to 太陽所至爲流泄禁止，病之常也; each begins 某氣所至 and most end with a phrase that names the category of what it has described — 時化之常、司化之常、氣化之常、德化之常、布政之常、氣變之常、令行之常、病之常. Then comes the sentence that gathers them: 凡此十二變者，報德以德，報化以化，報政以政，報令以令，氣高則高，氣下則下，氣後則後，氣前則前，氣中則中，氣外則外，位之常也. The rule is one of answering in kind: a year that was generous gets generosity, a year that was harsh gets harshness. This is what the opening question about 六化六變 has been waiting for.