| impugn | 责难，攻击，抨击：attack as false |
| impuissance | 无权，虚弱：lack of power |
| inadvertent | 偶然发生的：by chance；疏忽的，不留意的：unintentional lack of care |
| inalienable | 不可剥夺的，不能让与的：cannot be transferred |
| inane | 空洞的：lacking significance |
| inanimate | 无生命的：not living |
| inaugurate | 使就职：induct into an office；开始：begin |
| incandescent | 明亮灿烂的：bright；热情饱满的，感情强烈的：zeal |
| incantation | 咒语：magic power |
| incarnate | 化身的，人性化的：bodily nature and form；使（思想、理论）具体，体现：constitute an embodiment |
| incendiary | 煽动者：person who stirs up；煽动性的：tending to inflame |
| incense | 芳香：pleasant smell；激怒：extremely angry |
| inception | 开端，开始：beginning |
| incessant | 无间断的：without interruption |
| inch | 少量，很短的距离：small degree；（使）慢慢移动：move slowly |
| inchoate | 新生的，才开始的：early stage；未完全成型的：imperfectly formed |
| incinerate | 将…烧成灰烬：burn to ashes |
| incipient | 起初的，初现的：beginning to come into being |
| incite | 煽动，激起：provoke |
| inclement | （天气等）恶劣的：lacking mildness；无情的，残酷的：unmerciful |
| incogitant | 考虑不周到的，不体谅的：inconsiderate |
| incongruent | 不全等的；不一致的：not conforming |
| inconsequential | 不合逻辑的：not following good reasoning；不重要的：no significance |
| incontrovertible | 无可争议的：not open to question |
| incorrigible | 不可救药的，积习难改的：incapable of being corrected；无法管制的：impossible to control |
| incriminate | 归罪于：accuse of a crime |
| incubate | 孵化：cover and warm eggs；帮助，培养，促进：aid |
| inculpate | 归罪于：incriminate |
| incursion | 入侵：hostile entrance |
| indelible | （印记等）无法擦除的：impossible to remove；无法忘怀的：not easily forgotten |
| indemnity | （损害、伤害等的）保险赔偿：compensation |
| indict | 起诉，控告：accuse |
| indifferent | 公平的：impartiality；（质量、档次等）中规中矩的，一般的：average；不感兴趣的，冷漠的：lack of interest |
| indigenous | 土产的，本地的：originating；与生俱来的，先天的：innermost nature |
| indigent | 贫穷的：lacking money |
| indispensable | 必不可少的，不可或缺的：impossible to do without |
| indoctrinate | 教育，灌输思想：instruct |
| indolent | 懒惰的：averse to activity |
| inducement | 动机，刺激源：motive；劝说，游说：pleading with someone to accept |
| indulgent | （对己）放纵的，（对他人）纵容的：given to indulgence |
| indurate | 铁石心肠的，冷酷无情的：a lack of sympathy；使变硬：physically firm；使习惯于（如艰苦或尴尬之境况）：withstand physical hardship |
| industrious | 勤勉的：diligent |
| ineffable | 难以表达的：incapable expressed |
| ineluctable | 无法逃避的，必然的：not to be avoided |
| inept | 愚笨的，荒谬的：lack of judgment；不恰当的，不合时宜的：not appropriate；不称职的，无能力的：incompetent |
| inert | （人）懒惰缺乏活力的；（物品）惰性的：sluggish, deficient |
| inevitable | 不可避免的，必然的：incapable avoided |
| inexorable | 无法劝阻的，不为所动的：not persuaded |
| infamous | 臭名昭著的：bad reputation |
| infatuate | 使迷恋：inspire unreasoning love |
| inferno | 大火：fire；地狱：resembles hell |
| infiltrate | 秘密潜入：enter surreptitiously |
| infinite | 无尽的，无限的：no boundaries |
| infirm | 虚弱的：weak in body；不果断的，优柔寡断的：lacking firmness of will |
| inflame | 点燃，燃烧：set on fire；使加剧：more violent |
| infelicitous | 不愉快的，不幸的：unfortunate；不恰当的，不合时宜的：not appropriate |
| influx | 涌入：coming in |
| infuse | 激怒：make furious |
| infuriate | 灌输，使…充满：fill；鼓舞：inspire |
| ingenious | 聪明的，有创造才能的：resourceful, cleverness |
| ingenuity | 独创性，创新性：inventive |
| ingenuous | 天真纯朴的：lacking cunning；坦白的：straightforward |
| ingest | 摄入，咽下：take into body |
| ingrained | 本质的，根深蒂固的：firmly established |
| ingratiating | 讨人喜欢的：winning favor；逢迎的，意在奉承的：gain favor |
| inherent | 内在的，本质的：essential |
| inimical | 带有敌意的：hostility；危及某人利益的，不利的：opposed to interests |
| inimitable | 无法效仿的，独特的：not imitated |
| iniquity | 邪恶，不公正：immorality, injustice |
| initiate | 创造，发动促进：cause beginning；刚入门的新手：person initiation |
| inkling | 轻微暗示，小提示：slight indication；略知：vague notion |
| innocuous | 无害的：no injury；乏味的，不会引起敌意的：not arouse |
| innovative | 创新性的：introducing innovations |
| inquisitive | 过分好奇的：inordinately curious |
| insensible | 无知觉的：lost consciousness；漠不关心的：not responsive；粗俗的，没品味的：lacking in refinement |
| insensitive | 缺乏机智圆滑的，缺乏社交技巧的：lacking tact；不敏感的，麻木的：not responsive |
| insentient | 无感觉的，无知觉的：lacking perception；一知半解的，略懂的：not having a deep understanding |
| insight | 深刻的理解：apprehending nature |
| insipid | （食品）清淡无味的：lacking favor；平淡的，无聊的：lacking interest |
| insolent | 粗野的，无礼的：rude |
| insouciant | 无忧虑的，不在乎的：free from concern |
| instate | 任命：establish rank |
| instigate | 煽动，激起：urge forward, stir up |
| instill | 慢慢滴入：enter；灌输：impart |
| institute | 创立，制定：establish；机构：organization |
| insubordinate | 不服从权威的：not submissive |
| insular | （观念、想法等）孤立狭隘的：narrow provincial viewpoint |
| insulate | 使绝缘，使隔离：detached situation |
| insurgent | 叛乱分子：opposes authority |
| intangible | 无法感知的，无形的：capable perceived |
| integral | 构成整体所必需的：essential；完整的：not lacking any part |
| integrity | 正直：adherence moral；完整性：being whole |
| intelligible | 可理解的：being understood |
| intemperate | 无节制的，极端的，不温和的：not temperate |
| intensify | 加强，激化：make intense |
| inter | 埋葬：place in grave |
| intercessor | 调停者：mediates |
| interdict | 禁止：forbid；阻止：stop, seize or interrupt |
| interim | 中间过渡时期，间隔：time between event；暂时的：for the time being |
| interlock | 连锁，连结：joined closely |
| interminable | 无尽头的：no end |
| intermittent | 间歇的，断断续续的：not continuous；不定期的：lacking regularity |
| interregnum | 过渡期：break |
| interrogate | 质问，审问：question formally |
| intimate | 有紧密联系的，亲密无间的：close association；不为人知的：not known；密友：person who has a strong liking；迂回地交流，间接地沟通：communicate indirectly |
| intimidate | 威吓：frighten |
| intoxicant | 使人陶醉的东西（尤指酒精饮料）：intoxicates |
| intransigent | 不妥协的，固执的：refusal to compromise |
| intrepid | 无谓的：resolute fearlessness |
| intrigue | 阴谋：a secret plan；激起…的兴趣：arouse curiosity |
| intrinsic | 固有的，内在的：essential |
| intuitive | 直觉的：by intuition |
| inundate | 淹没：cover with flood |
| inure | 使习惯接受不好的东西：accustom；使坚强：withstand physical hardship |
| invective | 侮辱性的：characterized by insult |
| inveigh | 激烈抗议，表示强烈不满：protest vehemently |
| inveigle | 诱骗：win over by coaxing |
| inventory | 存货清单：list all goods；（包含要点的）简介：short statement |
| inveterate | 积习的：firmly established |
| invidious | 惹人反感的：cause discontent；羡慕嫉妒恨的：resentment of another’s possessions |
| invigorate | 使精神，使强壮，鼓舞激励：impart vigor |
| invincible | 不可战胜的，不可超越的：incapable conquered |
| invoke | 实施：put into effect；产生，造成：be the cause |
| irascible | 易怒的：easily provoked anger |
| irate | 极其愤怒的：extremely angry |
| iridescent | 五颜六色的：lustrous colors |
| irk | 令人烦恼的事物：source of irritation；使烦恼，使厌倦：irritating |
| ironclad | 非常坚固的，坚不可摧的：unbreakable |
| irradicable | 不能根除的：impossible destroy |
| irreducible | （数）不可约分的：incapable factored |
| irrigate | 灌溉：supply water；冲洗：flush |
| irritate | 刺激，惹恼：provoke anger |
| issue | （有争议的）话题，议题：matter that is in dispute；发布（期刊）等：produce and release；（使）流出：flow out |
| jabber | 快而不清楚地说：talk rapidly, indistinctly |
| jaded | 疲惫的：depleted in strength；厌倦的，没兴趣没热情的：patience exhausted |
| jape | 嘲弄：mockingly |
| jargon | 行业术语：specialized or technical language |
| jarring | 刺耳的：discordant；震惊的：strong emotional reaction |
| jaundice | （因嫉妒或厌世而产生的）偏见：bias |
| jaunty | 轻快呃，活泼的：sprightly |
| jejune | 无趣乏味的：not interesting；幼稚的：annoying qualities children |
| jettison | 丢弃，投弃：cast |
| jeopardy | 危险： risk, danger |
| jest | 轻浮的态度，戏谑：frivolous |
| jibe | 意见一致：agree |
| jingoist | 极端爱国激进分子（通常表现为好战的对外政策）：extreme nationalism belligerent |
| jitters | 紧张，不安：panic, nervousness |
| jocular | 搞笑的，欢乐的：joking, playful |
| jocund | 欢快的，高兴的：sprightly lighthearted |
| jog | 慢跑：movement exercise；唤起：rouse |
| jolt | 突然移动：move sudden；惊吓：unpleasant surprise |
| jot | 简要记录：write briefly |
| jovial | 愉快的：good-mannered, jollity, conviviality |
| jubilant | 喜悦的：joyful |
| judicious | 明智的，慎重的：judgment prudent |
| juggernaut | 无法阻挡的力量的，摧毁一切的强大力量：overwhelming force |
| ken | 视野范围：vision；知道，了解（人或物）：know |
| kidnap | 绑架勒索：detain unlawful force |
| kindle | 点燃：set fire, ignite |
| kindred | 类似的；具有相似或相近的起源、本性或性质的：similar origin |
| knack | 诀窍，聪明的做法：clever |
| knead | 揉捏，塑造：shape by folding |
| knit | 编织（纱线）：interlacing yarn with needles；连接，联系：join closely |
| knotty | 多结的，复杂的，困难的：full of difficulties complications |
| kudos | 名望，名声：fame；夸奖，赞扬：acclaim or praise |
| labile | 易变的，不稳定的：unstable |
| laborious | 勤奋的：industrious；费力的：long, hard work |
| labyrinthine | 迷宫似的，复杂曲折的：extremely complex structure |
| lacerate | 使非常痛苦：cause pain |
| lackluster | 黯淡无光泽的：lacking brightness |
| laconic | 简洁（以至于显得粗鲁或难以理解的）：minimum of words, concise |
| lachrymose | 催人泪下的，悲伤的：mournful |
| lambaste | 严厉斥责：scold sharply |
| lament | 悼词：composition grief；抱怨：resentment；为…哀悼，表达痛苦或遗憾：express sorrow |
| lamentable | 值得惋惜的，悲哀的：deplorable |
| lampoon | 讽刺：harsh satire |
| languid | 没精打采的，虚弱的：lacking energy |
| languish | 变得衰弱：become feeble |
| languor | 懒惰：inertness；衰弱：weakness, weariness |
| lank | 细长瘦弱的：long lean；不僵硬的，柔软松弛的：limp, not stiff |
| lapse | 小过失：slight error；结束，终止：end |
| largesse | 捐赠物：without expectation of a return；慷慨：liberality |
| lash | 击打：hard strike；猛击，撞击：strike with force；捆扎：bind |
| lassitude | 乏力，没精打采：diminished energy |
| latent | 潜在的，不活跃的：potential, not evident |
| latitude | （行动或言论）自由：freedom |
| laudatory | 表示赞扬的：praise |
| lavish | 奢侈的，大量的，无节制的：extravagance and profusion；挥霍，浪费：give readily carelessly |
| leaven | 在…中加入轻松、活泼或变更的因素：mingle permeate |
| leer | 一瞥，斜眼看：sidelong |
| leery | 怀疑的，不信任的：suspicious |
| legacy | 遗产：handed down ancestor |
| legend | 传奇，传说：popular myth；图例：explanatory list map |
| legion | 大量的人，（尤指）军团：large body of men；大量的：numerous |
| lenient | 宽大仁慈的：merciful |
| lethal | 非常有害的，致命的：extremely harmful |
| lethargic | 没精打采的，行动迟缓的：sluggish |
| levelheaded | 明智的：sensible |
| levity | 轻浮：frivolity |
| liability | 责任：liable；障碍，不利条件：creates difficulty |
