American Heritage Dictionary
(3)
Century Dictionary
(13)
GNU Webster's 1913
(3)
WordNet
(4)
Elsewhere on the web
When those photos were blown up, it became apparent that the speck was a bat.— ABC News: ABCNews
I shouldn't wonder if there wa'n't a speck of it in the house Not a speck was there to be found Your uncle's pockets must ha' had a good hole in 'em by this time," remarked Barby, as they came back from the cellar.— Queechy, Volume I
On the contrary, her detention of our posts, seems to be the speck which is to produce a storm.— Memoir, Correspondence, And Miscellanies, From The Papers Of Thomas Jefferson, Volume 1
This speck is the organ, and the organ is the sentient circumference drawn inwards, far within itself, according to a law which (however unconscious we may be of its operation) presides over every act and exercise of vision--a law which, while it contracts the sentient sphere, throws, at the same time, into necessary objectivity every phenomenon that falls external to the diminished circle.— Blackwood's Edinburgh Magazine — Volume 54, No. 337, November, 1843

American Heritage Dictionary (1)
Century Dictionary (3)
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