词根：cis(cas, chis), cide = to cut（切）
cis和cid是一对同源异形根，来自拉丁动词caedere, 意为 to cut（切）。cid是不定式词干，cis是动名词词干。其变形为cas 和chis。同义词根有来自拉丁语的torn(tem) ,scind/scis,sect,sever,tail,tons,trench,cop/coup等。
同源词：
1. concise（好好地切的 con<com(=intensive) + cis(=cut)）
adj.简洁的；简明的
conciseness n.简洁
concisely adv.简洁地
Class,please write concise answers to the essay questions. 同学们，请简要写出这篇文章问题的答案。
2. excise（切掉 ex(=out) + cis(=cut)）
vt. 切除；删除
n.国内消费税，货物税
excision n.切除；删除
He insisted that the violent scenes be excised from the film. 他坚持应删除电影中的暴力场面。
3. incisive（砍向里面或内部的 in(=in,into) + cis(=cut) + -ive 形容词后缀）
adj.锐利的，尖锐的；激烈的；敏感的；果断的
incision n.切割，切开；切口
incisor n.门牙
incise v.切割；雕刻，铭刻 《in- = in》
She's an incisive editor and cuts right to the bone. 她是一个果断的编辑，修改删节大刀阔斧。
4. circumcision
n.（尤其指犹太等为男婴施行的）割礼；割包皮 *circum(=around)
circumcise v. 为...割包皮；为...行割礼
He was never circumcised,and i feel his uncircumcised penis is a turn off to women. 他没有做过包皮切除手术，我想女人们因此而离开他。
5. decisive
adj.决定性的，决定的；坚决的；确定的 *de(=down)
decisively adv.决定性地
decisive battle 决战
decisive evidence 确证
decisive ballots 决选投票
6. precis
n. <法>大意，概略，摘录 *pre(=before,intensive)
vt. <法>为…写摘要，概括…的大意
7. precise
adj.精确的；确切的；细致的，严格；刻板的 *pre(=before,intensive)
precise measurements 精确的测量
a very precise man 非常刻板的人
8. precisely
adv.精确地；一丝苟地；（用于肯定回答）对，确实如此
9. chisel
n.凿子，凿刀 v.用凿子凿、刻、雕 *chis<cis(=cut)
10. castration
n.阉割，删改 *cas<cis(=cut)
castrate v.阉割；删改
11. fratricide
n.杀害兄弟姐妹者《fratri = 拉丁文frater = trother》 cf.fraternity （手足之情）
12. insecticide
n.杀虫剂《insect = 昆虫》
13. matricide
n.杀母者《matr = 拉丁文 mater =mother》 cf.maternity （母性）
14. patricide
n.杀父者 《patri = 拉丁文 pater =father》 cf.paternity （父性）
15. suicide
v.,n. 自杀（者）（将自己切割）《拉丁文su- = self》
16. bactericide（bacteri = bacteria 细菌；-cide n. = killer 杀...剂）
n. 杀菌剂
bactericidal adj.杀菌的
词根词缀：aphidi-, aphid-, aphis
【来源及含义】Latin: a plant louse; a plant sucking insect
【相关词根词缀】 A cross reference of other word family units that are related directly, or indirectly, with: "insects, bugs, worms; invertebrates": api-; ascari-; culci-; Dung Beetle Survival; Dung Beetles Important; Eating Worms; entomo-; formic-; Guinea worms; helmintho-; insecto-; Insects: Importance; isopter-; larvi-; lepidopter-; meliss-; mosquito; Mosquito, other Languages; Mosquitoes, Pt. 1; Mosquitoes, Pt. 2; myrmeco-; scarab; scoleco-; sphec-; taeni-; termit-; vermo-.
【同源单词】aphidian, aphidicide, aphidicole, Aphididae, aphidivorous, aphidophagous
词根词缀：arch, -archic, -archical, -archism, -archist, -archy
【来源及含义】Greek: govern, rule; ruler, chief [first in position]
【同源单词】anarch, anarchic, anarchism, anarchist, anarchy, antimonarchy
词根词缀：hiat-; -hisc-
【来源及含义】Latin: to stand open, to split; opening, aperture, gap; to yawn
【相关词根词缀】 A cross reference of other word family units that are related directly, indirectly, or partially with: "opening, hole, cavity, tract, tube": alveolo-; antro-; anu-; celo-; coelio-; concho-; fenestra-; hernio-; meato-; ora-; parieto-; poro-; pyl-, pyle-; pylor-; sphinctero-; splanchn-; stomato-; syringo-; uretero-; urethro-; vagino-; ventricul-.
【同源单词】dehisce, dehiscence, dehiscent, hiant, hiatal, hiation
词根词缀：histio-
【来源及含义】Greek: web, cloth, tissue
【相关描述】Many etymologically related words with the same family meanings with slightly different spellings are available at this histo- unit of words.
【同源单词】histiocyte, histiocytoma, histioid, histio-irritative, histionic, histocytosis
词根词缀：histo-, hist-, histi-
【来源及含义】Greek: tissue [web]; beam or warp of a loom; hence, that which is woven; a web or tissue; used in the sense of pertaining to [body] tissue
【同源单词】histaffine, histaminase, histamine, histamine blocking agent, histamine phosphate, histaminia
词根词缀：histor-, histori-
【来源及含义】Greek > Latin: historical narrative; past events, past knowledge
【相关词根词缀】 Inter-related cross references, directly or indirectly, involving word units meaning "know, knowledge; learn, learning": cogni-; discip-; gno-; intellect-; learn, know; math-; sap-; sci-; sopho-.
【同源单词】ahistorical, ethnohistorian, ethnohistoric, ethnohistorical, ethnohistory, future history
词根词缀：kathis-, cathis-, kathiso-, cathiso-
【来源及含义】Greek: to sit; sitting
【同源单词】acathistus, akathisia, kathisomania, kathisophobia
词根词缀：-mach, -machy, -machies, -machia, -machist, -machic, -machical
【来源及含义】Greek: battle, war; fight; contest
【相关词根词缀】 Related "war, war-like" or "battle" word units: areo-; belli-; milit-.
【同源单词】alectryomachy, andromachy, angelmachy, arctomachy, batrachoherpetomachia, batrachoherpetomachy
词根词缀：morpho-, morph-, -morphous, -morphically, -morphia, -morphosis, -morphously, -morphy, -morphic, -morphism
【来源及含义】Greek: shape, form, figure, appearance
【相关描述】The Roman god of sleep is Somnus; so, when we are sleepy, we are "somnolent". Sleep walking is "somnambulism" which in Latin means exactly the same thing; that is, "sleepwalking".
The son of Somnus is Morpheus, the god of dreams, indicating that sleep gives birth to dreams. Morpheus goes back through Latin to the Greek word for "form" or "shape" because dreams are forms and shapes developed in the mind while sleeping.
【相关词根词缀】 Inter-related cross references, directly or indirectly, involving word units dealing with "form, shape, appearance": eido-; figur-; form-; icono-; ideo-; imag-; -oid; typo-.
【同源单词】acrostomorphilia, actinomorphic, actinomorphous, actinomorphy, adelomorphous, aeromorphosis