(Latin: suffix; able manner, capably)

Forming adverbs corresponding to adjectives in -able.

incontestably (adverb), more incontestably, most incontestably
1. Conveying how something is beyond being debatable or challenged: It is incontestably true that Sam didn't pass the exam because he answered all the questions incorrectly!
2. Relating to how it is impossible to question the accuracy of a fact because of its being obviously correct: It is incontestably true that the earth rotates around the sun.
3. Etymology: from Latin incontestabilis, from in-, "not" + contestabilis, "arguable."
incurably (adverb), more incurably, most incurably
1. Descriptive of how an ailment is impossible to remedy: After Dr. Smith made his diagnosis, he told Mrs. Johnson that she was incurably ill and had only a few more years to live.
2. Characteristic of how a person is hopelessly incorrigible: Kitty always seemed to be such an incurably optimistic and happy person.
indefinably (adverb), more indefinably, most indefinably
Pertaining to how something is impossible to describe or to explain: Erin has an indefinably alluring personality which attracts many people to his musical performances.
indescribably (adverb), more indescribably, most indescribably
Concerning how something is beyond depiction, especially because of being extremely good or bad; unspeakably; unutterably: The cake served at the bakery was indescribably delicious!
indispensably (adverb), more indispensably most indispensably
Relating to how something is absolutely required or essential: In order for Clive to have a firm and healthy body, his personal trainer said that exercising at the gym was indispensably necessary.
indisputably (adverb) (not comparable)
A description of how a fact or certain knowledge is beyond doubt; undeniably: It is indisputably true that most birds can fly, and that snow is white is also indisputably true!
indistinguishably (adverb), more indistinguishably, most indistinguishably
Pertaining to how two things cannot be differentiated from each other: The indistinguishably-perfect gem could not be perceived to have any flaws whatsoever, and the specialist could not spot any dissimilarities from the genuine one at all!
indubitably (adverb), more indubitably, most indubitably
Referring to how something is without doubt; unquestionably: Their summer vacation in Greece was indubitably the most perfect and fantastic time Jack and Jill had ever had together!
ineffably (adverb), more ineffably, most ineffably
1. Descriptive of how something is indescribable: The poems Mrs. Smithson wrote were ineffably touching.
2. Concerning how something is incapable of being expressed in words: Jane was ineffably sad and depressed and missed her mother who had died recently after suffering so much.
ineluctably (adverb), more ineluctably, most ineluctably
Describing how something is inescapable or unavoidable: It is ineluctably true and inevitable that one day each living being must die.
inestimably (adverb), more inestimably, most inestimably
Descriptive how something is incapable of being approximated or rated: Every human life is certainly inestimably valued and extremely precious.

The universe is inestimably vast and boundless and cannot be measured!

inevitably (adverb), more inevitably, most inevitably
Descriptive of how something cannot be avoided and is certain to happen: Strong arguments between individuals often and inevitably result in tears, especially when the conflict includes insults.
inexcusably (adverb), more inexcusably, most inexcusably
1. Pertaining to how a behavior is unpardonable: Tom was inexcusably rude towards his wife and treated her in an unforgivable way and soon after they were divorced.
2. Concerning how something is without any justification or reasonable explanation: Jack was known to be inexcusably late to all of his classes.
inexorably (adverb), more inexorably, most inexorably
Concerning how something continues without any possibility of being stopped: The tornado or twister was raging and advancing inexorably towards the little village.

Each day moves on inexorably to the next day, and each month proceeds inexorably to the next month.

inexpiably (adverb), more inexpiably, most inexpiably
Expressing how something cannot be pardoned; unforgivably: The thief stole the jewels, threatened and wounded the home owner inexpiably, and fled from the scene.