They are false cognates. You are right that cognates are words that
sound the same and mean nearlt the same things. False cognates are words
that sound alike and thus mught fool one into believing that they are
cognates. The two words sound very similar and have different meanings
(although many who grew up in ranch land might argue that cow and
fool/stupid are not all that far apart.) I was not implying that baka
meant cow, but that it has a similar sound to vaca and thus can be said
to be a verbal (although not a written) false cognate. Sigh. I got the
definition of false cognate pounded into my head repeatedly by a
deceptively jovial French prof and by a particularly enthusiastic Old
English prof. Since then I've developed a habit of noting them whenever
I go after a new language (Hebrew and Japanese are next on my list).

(Shakes head _very_ profusely)
*BZZZZZZZT!*
Sorry, both you and your professors were (almost) wrong. You might have
been "pounded" with this meaning of a cognate by those professors, but _I_
took a linguistics course. _I_ know what I'm talking about. Your professors
missed one thing that makes "baka" and "vaca" not cognates.

True cognates are words in a language derived from the _same root_! (that's
why they're almost the same in meaning. Usually) False cognates are as you
say, but they also must be formed from completely different roots. And
there is a qualifier:

THE LANGUAGES MUST BE FROM THE SAME FAMILY and/or THEY MUST BORROW ROOTS
FROM ONE ANOTHER.

English and French appear very different, but they're _both_ Indo-European
languages. Ultimately, all those words stem from the same set of roots. Not
only that, English borrows heavily from French. It's been that way since
Agencord (sp?). There are cognates, true and false, galore between
langauges.

Japanese is related to no other language in the world. You would therefore
not expect ANY words to share any roots, and any similar sounding words
would just be coincidence. Only if there are a lot of true cognates between
langauges can there be false ones.

For example, "bed" (E) and "Bett" (G) are derived from the same root
("bedd"), and both mean "bed". It's a true cognate. Both English and German
are Germanic languages. An example of a false cognate is "name" (E) and
"nehmen" (G). "nehmen" means "take"; we got our original word for "take",
"namen" and replaced it with a French word. Hence, the false cognate.

"Ohayo" and "Ohio" are similar sounding, but are not cognates because,
being completely unrelated to each other and lack borrowing (at least until
recently), they share no roots and thus you shouldn't expect there to be
any similarity in meaning. Similarly with "baka"/"vaca". A student would
(or at least should) not be easily fooled because she knows that the two
languages are not related.

QED

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