He may put in just enough effort to learn some trivia to impress
Is the need to impress others with something that isn't a total fabrication the most important aspect of the word you are searching for?
Is it alright if the word is vulgar slang?
If you answered yes to both, then search no more, here's part of Wikipedia's discussion on the subject matter
Distinguished from lying
"Bullshit" does not necessarily have to be a complete fabrication;
with only basic knowledge about a topic, bullshit is often used to
make the audience believe that one knows far more about the topic by
feigning total certainty or making probable predictions. It may also
merely be "filler" or nonsense that, by virtue of its style or
wording, gives the impression that it actually means something.
In his essay on the subject, William G. Perry called bull[shit]
"relevancies, however relevant, without data" and gave a definition of
the verb "to bull[shit]" as follows:
- To discourse upon the contexts, frames of reference and points of observation which would determine the origin, nature, and meaning of
data if one had any
- To present evidence of an understanding of form in the hope that the reader may be deceived into supposing a familiarity with
The bullshitter generally either knows the statements are likely
false, exaggerated, and in other ways misleading or has no interest in
their factual accuracy one way or the other. "Talking bullshit" is
thus a lesser form of lying, and is likely to elicit a correspondingly
weaker emotional response: whereas an obvious liar may be greeted with
derision, outrage, or anger, an exponent of bullshit tends to be
dismissed with an indifferent sneer.
Oxford English Dictionary has this to say
noun, vulgar slang
- Stupid or untrue talk or writing; nonsense. verb (bullshits, bullshitting, bullshitted)
- Talk nonsense to (someone), typically to be misleading or deceptive.