blur

Etymology

From earlier blurre, probably an alteration of blear, from Middle English bleren, from Old English *blerian (attested in āblered (“made bare, made bald”)), from Proto-West Germanic *blaʀjan, from Proto-Germanic *blazjaną (“to make pale”), from Proto-Germanic *blasaz (“pale”). Compare Scots blore, bloar (“to blur, cover with blots”), Low German bleeroged (“blear-eyed”). More at blear.

verb

1. To make indistinct or hazy, to obscure or dim.
   to blur a photograph by moving the camera while taking it
2. To smear, stain or smudge.
   to blur a manuscript by handling it while damp
3. (intransitive) To become indistinct.
4. To cause imperfection of vision in; to dim; to darken.
   His eyes are blurred with the lightning's glare. 1819, Joseph Rodman Drake, The Culprit Fay
5. (obsolete, transitive) To sully; to stain; to blemish, as reputation.
6. (graphical user interface, transitive) To transfer the input focus away from.
   Then give this box focus to blur the first one: […] 2003, John Pollock, JavaScript: A Beginner's Guide, Second Edition, page 175
   These form elements need to have an onFocus event handler to blur the current focus. 2001, Martin Webb, Michel Plungjan, Keith Drakard, Instant JavaScript, page 678
   Blurring one window and focusing on another window yields the same result of sending the window to the back of the pile. 2007, Danny Goodman, JavaScript Bible, page 273
   A manual way to blur a text object is to press the Tab key, which advances focus to the next field in order and removes it from the current field (blurring it). 2010, Chuck Easttom, Advanced Javascript, page 329
7. (copyright law) To use a sign, image, expression, etc. sufficiently close to a trademarked one that it causes confusion between them.

noun

1. A smear, smudge or blot.
2. Something that appears hazy or indistinct.
   The surroundings went by in a blur.
   Maccario, it was evident, did not care to take the risk of blundering upon a picket, and a man led them by twisting paths until at last the hacienda rose blackly before them. Appleby could see it dimly, a blur of shadowy buildings with the ridge of roof parapet alone cutting hard and sharp against the clearing sky. 1907, Harold Bindloss, chapter 26, in The Dust of Conflict
   Unfortunately, a small artificial pupil also tends to increase the amount of diffraction somewhat, but this increase in blur is considerably smaller than the decrease that results from the control of other factors. 1978, Stanley Coren, Joan S. Girgus, Seeing Is Deceiving: The Psychology of Visual Illusions, Lawrence Erlbaum Associates, Inc., page 82
   The fightback when it came was in the [Roger] Federer fashion: unfussy, filled with classy strokes from the back with perfectly timed interventions at the net that confounded his opponent. The third set passed in a bit of a blur, the fourth, which led to the second tie-break, was the most dramatic of the match. 29 June 2012, Kevin Mitchell, “Roger Federer back from Wimbledon 2012 brink to beat Julien Benneteau”, in The Guardian, archived from the original on 2016-11-15
   The second option (right-hand page) features a sharp background and a cyclist who appears as a smudge of blur. 2014, Albrecht Rissler, Photographic Composition: Principles of Image Design, Rocky Nook, Inc.
   Selectively applying blur to the edges can give the impression of a toy camera or a tilt-shift lens. 2016, Kat Sloma, Art with an iPhone: A Photographer’s Guide to Creating Altered Realities, Amherst Media
3. (obsolete) A moral stain or blot.
   […]with her raillyng sette a great blurre on myne honesty 1548, Nicolas Udall, The first tome or volume of the Paraphrase of Erasmus vpon the newe testamente

adj

1. (Malaysia, Singapore, informal) In a state of doubt or confusion.