词根：rol = ring, circle 圆, 环, 滚动
词根rac的含义是字母 r 本意的引申义，可以理解为一个像圆一样的旋转，卷。有异形同义词根：-circ-，-cycl- 圆，环。
词根扩展：自己比较喜欢自动旋转的圆环：aut，auto 自己，自动，自身，来源于希腊语 autos，分别用于元音和辅音前，如：autocide 自杀，自我毁灭、autoalarm 自动报警器。
同源词：
1. roll [l( 形似 ) 表示 1 → 一张纸旋转一周 →]
n.卷，滚动，卷形物，名单
v.摇摆；滚；绕；转动；展开
2. enroll [en- 使 + roll =rol →使旋转滚动进入某个组织，机构等→]
v.登记；招收；入伍
3. stroll [str(=street) 街 + roll =rol转 → 一个人在街上不停的转圈 →]
v.& n. 散步
4. reel [reel= rol，即旋转]
v. 旋转，卷…于轴上
5. payroll [pay 薪水 + roll 名单 →]
n.薪水册
6. role [来源古典（以前演员都是拿着一卷牛皮纸背台词，参加演出的，此词是它的引申义，即角色，任务）]
n. 角色，任务
前缀：auto- 自己, 自动
autocriticsm 自我批评
autorotation 自动旋转
autoalarm 自动报警器
autosuggestion 自我暗示
autoinfection 自体感染
anto-timer 自动定时器
autobike 机器脚踏车
词根词缀：ger-, ges-, gest-
【来源及含义】Latin: carry, produce; to bear
【相关描述】Don't confuse this ger- with another Greek gero-, ger- which means "old age".
【相关词根词缀】 Cross references of word families related to "bear, carry, bring": duc-; -fer; later-, -lation; phoro-; port-.
【同源单词】autosuggestion, belligerence, belligerency, belligerent, belligerently, cobelligerent
词根词缀：nous-, nou-, noe-, noes-, noet-, -noia
【来源及含义】Greek: mind, intellect; the reason; common sense
【相关词根词缀】Inter-related cross references, directly or indirectly, involving the "mind, mental" word units: anima-; anxi-; deliri-; hallucina-; menti-; moro-; noo-; phreno-; psych-; thymo-2.
【同源单词】anoesis, anoetic, autosynnoia, dianoetic, dianoia, jealous-type paranoia
词根词缀：sero-, ser-, seri-
【来源及含义】Latin: serum, whey; watery substance; serum, in connection with serum
【相关描述】Used primarily in the extended sense of "clear animal fluid".
【相关词根词缀】Serum, whey words: oro-, orrho- unit.
【同源单词】autoserotherapy, chemoserotherapy, mucoserous, seroconversion, seroculture, serodiagnosis
词根词缀：sitio-, siti-, sito-, sit-, -sitia
【来源及含义】Greek: food; eating; appetite
【相关词根词缀】 Cross references of word families that are related directly, or indirectly, to: "food, nutrition, nourishment": alimento-; broma-; carno-; cibo-; esculent-; tropho-; Eating Crawling Snacks; Eating: Carnivorous-Plant "Pets"; Eating: Folivory or Leaf Eaters; Eating: Omnivorous.
【同源单词】adelphoparasite, alloparasite, antiparasitic, apositia, asitia, autosite
词根词缀：spleno-, splen-, splenico-, spleni-, -splenism, -splenia, -splenic
【来源及含义】Greek: spleen, "the inward parts;" the elongated accessory lymphatic organ of the vascular [blood] system
【相关描述】The spleen is a large glandlike, but ductless, organ situated in the upper part of the abdominal cavity on the left side and lateral to the cardiac end of the stomach.
It is also called the lien. The largest structure in the lymphoid system, it is a flattened oblong shaped structure of about 125 mm. in length.
It disintegrates the red blood cells and sets the hemoglobin free, which the liver converts into bilirubin; it gives rise to new red blood cells during fetal life and in the newborn; serves as a reservoir of blood; produces lymphocytes and plasma cells; and has other important functions, the full scope of which hasn't been entirely determined.
【同源单词】asplenia, asplenic, autosplenectomy, Habet et musca splenem, hepatosplenitis, hepatosplenomegaly