Word Study
imperceptible
CIDE DICTIONARY
imperceptible, a. [Pref. im- not + perceptible: cf. F. imperceptible.].
Not perceptible; not to be apprehended or cognized by the senses; not discernible by the mind; not easily apprehended. [1913 Webster]
"Almost imperceptible to the touch." [1913 Webster]
"Its operation is slow, and in some cases almost imperceptible."
"Their . . . subtilty and imperceptibleness." [1913 Webster]
OXFORD DICTIONARY
imperceptible, adj.
1 that cannot be perceived.
2 very slight, gradual, or subtle.
1 that cannot be perceived.
2 very slight, gradual, or subtle.
Derivative
imperceptibility n. imperceptibly adv.
Etymology
F imperceptible or med.L imperceptibilis (as IN-(1), PERCEPTIBLE)
THESAURUS
imperceptible
atomic, behind the curtain, behind the scenes, camouflaged, concealed, corpuscular, disguised, embryonic, ephemeral, evanescent, faint, fugitive, germinal, granular, hidden, ill-defined, impalpable, imponderable, inappreciable, inaudible, inconsiderable, inconspicuous, indiscernible, indistinct, indistinguishable, infinitesimal, insensible, insignificant, intangible, invisible, latent, microcosmic, microscopic, minuscule, minute, molecular, momentary, obscure, out of sight, secret, sightless, slight, subatomic, submerged, subtle, tenuous, thin, tiny, trivial, ultramicroscopic, unapparent, unappreciable, unbeheld, unbeholdable, unclear, undiscernible, undistinguishable, unnoticeable, unnoticed, unobservable, unobserved, unperceivable, unperceived, unrealized, unseeable, unseen, unviewed, unwitnessed, vague, viewlessROGET THESAURUS
imperceptible
Littleness
N littleness, smallness, exiguity, inextension, parvitude, parvity, duodecimo, Elzevir edition, epitome, microcosm, rudiment, vanishing point, thinness, dwarf, pygmy, pigmy, Liliputian, chit, pigwidgeon, urchin, elf, atomy, dandiprat, doll, puppet, Tom Thumb, Hop-o'-my-thumb, manikin, mannikin, homunculus, dapperling, cock-sparrow, animalcule, monad, mite, insect, emmet, fly, midge, gnat, shrimp, minnow, worm, maggot, entozoon, bacteria, infusoria, microzoa, phytozoaria, microbe, grub, tit, tomtit, runt, mouse, small fry, millet seed, mustard seed, barleycorn, pebble, grain of sand, molehill, button, bubble, point, atom, fragment, powder, point of a pin, mathematical point, minutiae, micrometer, vernier, scale, microphotography, photomicrography, micrography, photomicrograph, microphotograph, microscopy, microscope (optical instruments), little, small, minute, diminutive, microscopic, microzoal, inconsiderable, exiguous, puny, tiny, wee, petty, minikin, miniature, pygmy, pigmy, elfin, undersized, dwarf, dwarfed, dwarfish, spare, stunted, limited, cramp, cramped, pollard, Liliputian, dapper, pocket, portative, portable, duodecimo, dumpy, squat, short, impalpable, intangible, evanescent, imperceptible, invisible, inappreciable, insignificant, inconsiderable, trivial, infinitesimal, homoeopathic, atomic, subatomic, corpuscular, molecular, rudimentary, rudimental, embryonic, vestigial, weazen, scant, scraggy, scrubby, thin, granular, shrunk, brevipennate, in a small compass, in a nutshell, on a small scale, minutely, microscopically.Slowness
N slowness, languor, drawl, creeping, lentor, retardation, slackening, delay, claudication, jog trot, dog trot, mincing steps, slow march, slow time, slow goer, slow coach, slow back, lingerer, loiterer, sluggard, tortoise, snail, poke, dawdle, slow, slack, tardy, dilatory, gentle, easy, leisurely, deliberate, gradual, insensible, imperceptible, glacial, languid, sluggish, slow paced, tardigrade, snail-like, creeping, reptatorial, slowly, leisurely, piano, adagio, largo, larghetto, at half speed, under easy sail, at a foots pace, at a snail's pace, at a funeral pace, in slow time, with mincing steps, with clipped wings, haud passibus aequis, gradually, gradatim, by degrees, by slow degrees, by inches, by little and little, step by step, one step at a time, inch by inch, bit by bit, little by little, seriatim, consecutively, dum Roma deliberat Saguntum perit, at a glacial pace.Invisibility
N invisibility, invisibleness, nonappearance, imperceptibility, indistinctness, mystery, delitescence, concealment, latency, invisible, imperceptible, undiscernible, indiscernible, unapparent, non-apparent, out of sight, not in sight, a perte de vue, behind the scenes, behind the curtain, viewless, sightless, inconspicuous, unconspicuous, unseen &c (see), covert, eclipsed, under an eclipse, dim, mysterious, dark, obscure, confused, indistinct, indistinguishable, shadowy, indefinite, undefined, ill- defined, ill-marked, blurred, fuzzy, out of focus, misty, delitescent, hidden, obscured, covered, veiled (concealed), full many a flower is born to blush unseen.For further exploring for "imperceptible" in Webster Dictionary Online