The act of irritating, or exciting, or the state of being irritated; excitement; stimulation, usually of an undue and uncomfortable kind; especially, excitement of anger or passion; provocation; annoyance; anger. [1913 Webster]
"The whole body of the arts and sciences composes one vast machinery for the irritation and development of the human intellect." [1913 Webster]
The act of exciting, or the condition of being excited to action, by stimulation; -- as, the condition of an organ of sense, when its nerve is affected by some external body; esp., the act of exciting muscle fibers to contraction, by artificial stimulation; as, the irritation of a motor nerve by electricity; also, the condition of a muscle and nerve, under such stimulation. [1913 Webster]
A condition of morbid excitability or oversensitiveness of an organ or part of the body; a state in which the application of ordinary stimuli produces pain or excessive or vitiated action. [1913 Webster]

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THESAURUS

irritation

adverse circumstances, adversity, affliction, aggravation, agitation, algesia, amplification, animation, annoyance, arousal, arousing, augmentation, blight, bummer, care, chafe, contentiousness, cross, curse, deepening, deliberate aggravation, deterioration, difficulties, difficulty, disapprobation, disapproval, discontent, displeasure, dissatisfaction, downer, electrification, embittering, embitterment, enhancement, enlargement, exacerbation, exasperation, excitation, excitement, exhilaration, festering, firing, fomentation, fret, gall, galvanization, hard knocks, hard life, hard lot, hardcase, hardship, heightening, incitation, incitement, increase, inflammation, infuriation, instigation, intensification, irritant, lathering up, magnification, pep rally, pep talk, perturbation, plight, predicament, pressure, provocation, rabble-rousing, rankling, resentfulness, resentment, rigor, sea of troubles, sensitiveness, sharpening, sore, sore spot, soreness, souring, steaming up, stimulation, stimulus, stirring, stirring up, stirring-up, stress, stress of life, tenderness, trial, tribulation, trouble, troubles, vale of tears, vexation, vicissitude, whipping up, working up, worsening

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ROGET THESAURUS

irritation

Excitation

N excitation of feeling, mental excitement, suscitation, galvanism, stimulation, piquance, piquancy, provocation, inspiration, calling forth, infection, animation, agitation, perturbation, subjugation, fascination, intoxication, enravishment, entrancement, pressure, tension, high pressure, unction, impressiveness, trail of temper, casus belli, irritation, passion, thrill, repression of feeling, sensationalism, yellow journalism, excited, wrought up, up the qui vive, astir, sparkling, in a quiver, in a fever, in a ferment, in a blaze, in a state of excitement, in hysterics, black in the face, overwrought, tense, taught, on a razor's edge, hot, red-hot, flushed, feverish, all of a twitter, in a pucker, with quivering lips, with tears in one's eyes, flaming, boiling over, ebullient, seething, foaming at the mouth, fuming, raging, carried away by passion, wild, raving, frantic, mad, distracted, beside oneself, out of one's wits, ready to burst, bouleverse, demoniacal, lost, eperdu, tempest-tossed, haggard, ready to sink, stung to the quick, up, on one's high ropes, exciting, absorbing, riveting, distracting, impressive, warm, glowing, fervid, swelling, imposing, spirit-stirring, thrilling, high-wrought, soul-stirring, soul-subduing, heart-stirring, heart- swelling, heart-thrilling, agonizing, telling, sensational, hysterical, overpowering, overwhelming, more than flesh and blood can bear, yellow, piquant, spicy, appetizing, provocative, provoquant, tantalizing, eager to go, anxious to go, chafing at the bit, till one is black in the face, the heart beating high, the heart going pitapat, the heart leaping into one's mouth, the blood being up, the blood boiling in one's veins, the eye glistening, the eyes in a fine frenzy rolling, the head turned, when the going gets tough, the tough get going.

Physical Energy

N energy, physical energy, force, power, keenness, intensity, vigor, strength, elasticity, go, high pressure, fire, rush, acrimony, acritude, causiticity, virulence, poignancy, harshness, severity, edge, point, pungency, cantharides, seasoning, activity, agitation, effervescence, ferment, fermentation, ebullition, splutter, perturbation, stir, bustle, voluntary energy, quicksilver, resolution, exertion, excitation, strong, energetic, forcible, active, intense, deep-dyed, severe, keen, vivid, sharp, acute, incisive, trenchant, brisk, rousing, irritation, poignant, virulent, caustic, corrosive, mordant, harsh, stringent, double-edged, double-shotted, double- distilled, drastic, escharotic, racy, potent, radioactive, strongly, fortiter in re, with telling effect, the steam is up, vires acquirit eundo, the race by vigor not by vaunts is won.

Pain

N mental suffering, pain, dolor, suffering, sufferance, ache, smart, passion, displeasure, dissatisfaction, discomfort, discomposure, disquiet, malaise, inquietude, uneasiness, vexation of spirit, taking, discontent, dejection, weariness, anhedonia, annoyance, irritation, worry, infliction, visitation, plague, bore, bother, botheration, stew, vexation, mortification, chagrin, esclandre, mauvais quart d'heur, care, anxiety, solicitude, trouble, trial, ordeal, fiery ordeal, shock, blow, cark, dole, fret, burden, load, concern, grief, sorrow, distress, affliction, woe, bitterness, heartache, carking cares, heavy heart, aching heart, bleeding heart, broken heart, heavy affliction, gnawing grief, unhappiness, infelicity, misery, tribulation, wretchedness, desolation, despair, extremity, prostration, depth of misery, nightmare, ephialtes, incubus, pang, anguish, agony, torture, torment, purgatory, hell upon earth, iron age, reign of terror, slough of despond, peck of troubles, ills that flesh is heir to, miseries of human life, unkindest cut of all, sufferer, victim, prey, martyr, object of compassion, wretch, shorn lamb, in pain, in a state of pain, full of pain, suffering, pained, afflicted, worried, displeased, aching, griped, sore, on the rack, in limbo, between hawk and buzzard, uncomfortable, uneasy, ill at ease, in a taking, in a way, disturbed, discontented, out of humor, weary, heavy laden, stricken, crushed, a prey to, victimized, ill-used, unfortunate, to be pitied, doomed, devoted, accursed, undone, lost, stranded, fey, unhappy, infelicitous, poor, wretched, miserable, woe-begone, cheerless, careworn, concerned, sorry, sorrowing, sorrowful, cut up, chagrined, horrified, horror-stricken, in grief, plunged in grief, a prey to grief, in tears, steeped to the lips in misery, heart-stricken, heart-broken, heart-scalded, broken-hearted, in despair, the iron entered into our soul, haeret lateri lethalis arundo, one's heart bleeding, down, thou climbing sorrow, mirth cannot move a soul in agony, nessun maggior dolere che ricordarsi del tempo fel, sorrow's crown of sorrow is remembering happier th, the Niobe of Nations.

Resentment

N resentment, displeasure, animosity, anger, wrath, indignation, exasperation, bitter resentment, wrathful indignation, pique, umbrage, huff, miff, soreness, dudgeon, acerbity, virulence, bitterness, acrimony, asperity, spleen, gall, heart-burning, heart-swelling, rankling, ill humor, bad humor, ill temper, bad temper, irascibility, ill blood, revenge, excitement, irritation, warmth, bile, choler, ire, fume, pucker, dander, ferment, ebullition, towering passion, acharnement, angry mood, taking, pet, tiff, passion, fit, tantrums, burst, explosion, paroxysm, storm, rage, fury, desperation, violence, fire and fury, vials of wrath, gnashing of teeth, hot blood, high words, scowl, sulks, affront, provocation, offense, indignity, grudge, crow to pluck, bone to pick, sore subject, casus belli, ill turn, outrage, Furies, Eumenides, buffet, slap in the face, box on the ear, rap on the knuckles, angry, wrath, irate, ireful, wrathful, cross, Achillean, sulky, bitter, virulent, acrimonious &c (discourteous), violent, warm, burning, boiling, boiling over, fuming, raging, foaming, foaming at the mouth, convulsed with rage, offended, waxy, acharne, wrought, worked up, indignant, hurt, sore, set against, fierce, wild, rageful, furious, mad with rage, fiery, infuriate, rabid, savage, relentless, flushed with anger, flushed with rage, in a huff, in a stew, in a fume, in a pucker, in a passion, in a rage, in a fury, in a taking, in a way, on one's high ropes, up in arms, in high dudgeon, angrily, in the height of passion, in the heat of passion, in the heat of the moment, Int, tantaene animis coelestibus irae!, marry come up!, zounds!, 'sdeath!, one's blood being up, one's back being up, one's monkey being up, fervens difficili bile jecur, the gorge rising, eyes flashing fire, the blood rising, the blood boiling, haeret lateri lethalis arundo, beware the fury of a patient man, furor arma ministrat, ira furor brevis est, quem Jupiter vult perdere dementat prius, What, drunk with choler?.

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