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Main Entry: dis.com.bob.u.late
Pronunciation: "disk&m'b@b(y)&"lAt
Function: transitive verb
Inflected Form(s): -ed/-ing/-s
Etymology: probably alteration of discompose or discomfit
: UPSET, CONFUSE, DISCONCERT <the offensive had discombobulated all the German
defensive arrangements -- A.J.Liebling>
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and if you buy the alteration theory, there's little likelihood of there ever having been a 'combobulate'. of course, we could always backformate it...