The precise origin of the blah is not stated, but it appears to have
arisen at the beginning of the 20th century and probably originated as
an imitation of the sound of talking.
According to Encarta, the origin is "early 20th century. An imitation
of the sound of somebody talking vacuously."
Etymonline.com states that blah (n.) meaning "idle, meaningless talk,"
was first noted in 1918, and was "probably echoic". It goes on to
state "the adj. meaning "bland, dull" is from 1919, perhaps infl. by
Fr. blasÚ "bored, indifferent." The blahs "depression" is first
The Webster?s Dictionary of 1913, makes no mention of the word.
Therefore, this seems to support its early 20th century origin.
Interestingly, Etymonline.com also provides information on some very
similar echoic words.
blather - 1524, Scottish, probably from a Scand. source, such as O.N.
blar "to chatter, babble," probably of imitative origin. Blatherskite
"talker of blatant nonsense" (1650) was popularized in U.S. during the
Revolution by the Scottish song "Maggie Lauder."
blab - 1535, from noun meaning "one who does not control his tongue"
(c.1374), probably echoic.
blabber (v.) - 1362, frequentative of blabben, of echoic origin.
Blabbermouth first recorded 1936.
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