[mhartl]

For better or for worse, the term bullshit has no exact synonym in the English language; we use the term because it precisely describes the phenomena we are studying.

Interestingly enough, the claim about bullshit lacking an exact synonym is false. Not only does bull by itself mean precisely the same thing, but in fact its use predates the compound formation by three centuries. The use of shit in bullshit is an intensifier, as in shitstorm or shitfit, though presumably the rather evocative image of bovine excrement was also a factor.

From the Google dictionary:

    bull (3)
    bo͝ol/
    noun informal
    noun: bull

        stupid or untrue talk or writing; nonsense.
        "much of what he says is sheer bull"

    Origin
    early 17th century: of unknown origin.


    bull·shit
    ˈbo͝olˌSHit/
    vulgar slang
    noun
    noun: bullshit

        1. stupid or untrue talk or writing; nonsense.

    Origin
    early 20th century: from bull (3) + shit.