备考资料：托福考试词汇研究－Unit4

　　astringent a.收敛性的;止血的 [stringent 严格的;严厉的]

　　astrolabe n.星盘

　　astrology n.占星学 [ASTRO-, -LOGY]

　　astute a.机敏的;狡猾的 [astut or  astutus astus craft]

　　asunder ad.散开;碎散;分别 [ on sundran into pieces: cf SUNDER分为二,分开,切开]

　　asylum n.收容所;避难所 [ asulon refuge a- not + sulon right ofseizure捕捉,扣押]

　　asymmetric a.不均匀的;不对称的

　　atheistic a.无神论者的 [atheism无神论]

　　athirst a.渴;渴望 [ ofthyrst for ofthyrsted pp. of ofthyrstan be thirsty]

　　athlete n.比赛者,运动家;强壮的人[ athleta athletes athleo contend for a prize(athlon)]

　　athletics n.pl.运动 [athlete运动员]

　　athwart ad.横穿过去;不顺利地 [A+THWART(古北欧语"横过")妨碍,反对,使挫折)]

　　atlas n.地图集 [ Atlas -antos a Titan who held up the pillars of theuniverse, whose picture appeared at the beginning] of [early atlases]

　　atomy n.微小之物;原子;矮人 [ANATOMY剖析;解剖学;骨骸 taken as an atomy]

　　atonal a.无调的

　　atone v.补偿;赎罪 [back-form ATONEMENT 赎罪 at one + -MENT, after medL  adunamentum and earlier onementobs] [one(v)unite]

　　atrocious a.凶暴的;残酷的 [atrox -ocis cruel atrocity暴行]

　　atrophy v.使衰退;使萎缩 [atrophie or LL atrophia a- not+trophe food]

　　attach v.附上,贴上;使属于 [estachier fasten: in Law sense thr. atachier]

　　attachment n.附着;依恋;逮捕;扣押 [ attachement attacher(ATTACH, -MENT)]

　　attainment n.成就;造诣;学识

　　attentive a.注意周到的;倾听的 [attente,  atente, fem pp. of atendre ATTEND]

　　attenuate v.使变细;使弱 [AD-, tenuis thin]

　　attest v.证明;证实 [AD-, testis witness]

　　attic n.阁楼 [attique, as ATTIC古怪的: orig a small order above a taller one]

　　attire n.服装;盛装;打扮 [atir(i)er equip a tire in order]

　　attorney n.代理人;律师 [ atorne pp. of atorner assignto+torner turn]

　　attribute n.品性 [ attribuere attribut-(AD-, tribuere assign)]

　　attrition n.摩擦;磨损 [attritio atterere attrit- rub]

　　attune v.使合拍调;使调和 [AT-+TUNE]

　　atypical a.非典型的;不正常的

　　auction v.n.拍卖;拍卖人 [ auctio increase, auction augere auct- increase]

　　audacious a.大胆的;目中无人的 [  audax -acis bold audere dare audacity胆识;大胆;无耻]

　　audible a.听得见的,可听见的 [audibilis audire hear. audibility 听得见,可听性]

　　audience n.听众;观众 [audire hear]

　　audit n.检查(项目) [audire audit- hear audition听觉;试听(歌手等)]

　　auditorium n.听众席,观众席;大讲堂 [ neut. of auditorius (adj.): AUDITORY, -ORIUM]

　　augment v.增加 [ augment(n), augere increase]

　　augury n.占兆 [ augurie or  augurium AUGUR]

　　august a.堂堂的;威风凛凛的 [ auguste or  augustus consecrated, venerable]

　　aural a.耳的;听觉的 [ auris ear auricular耳的;听觉的;耳语的]

　　aureate a.金色的;灿烂的 [ aureatus aureus golden aurum gold]

　　aureole n.光环 [aureola(corona), = golden(crown), fem of aureolus]

　　auroral a.北极光的 [AURORA 极光;夜晚女神]