What, if any, are the differences in meaning between "sport" and "sports"?

The correct usage of sport or sports is one test of a non-native's
English ability, and maybe of that of some natives.
Here is the way Wikipedia uses the words, but the site provides only
examples, not an explanation.
http://www.explainthat.info/cgi-bin/htsearch?restrict=;exclude=;config=xtop;method=and;format=Default;sort=score;words=sport%20vs%20sports;page=1

Here is another site that looked like it was going to discuss the
matter, but I did not find where it did after clicking on "sport vs
sports", but you may find the site of general interest:
http://www.vxu.se/hum/publ/gtn/Index(usagequestions).html

When America wakes up, I expect that someone will provide an answer.
Cheers, Myoarin

Then there's "money" and "monies," not to mention "fish" and "fishes."

Well, I am American.  I notice BBC News has a section called "Sport". 
This is jarring to my eyes.  Newspapers (including those online)
should have a Sports section.  BBC almost leaves one wondering "which
sport are they referring to?"  In U.S. usage "sport" refers to a
single sport.  "Sports" encompases the world of sports.

(There are times when "monies" can be used.  I loathe "fishes" and also "shrimps".)

Nelson...

Sorry to burst the bubble: it's "Sport". Get used to being wrong ;-).
Just like 'gas' and 'petrol'; 'center' and 'centre'; 'check' and
'cheque'; etc.

You guys.

We saved your butts in WWII.  I love British culture (I just saw Pride
& Prejudice starring Keira and it was briliant; I love BBC America),
but the wolrd looks to America for English-language culture.

Alas, here in Australia, "sport" tends to refer exclusively to
football, though there are several different football codes.

"Sports" covers all of them.

"The sport of kings", of course, is horse racing

"Sport" would refer to one 'physical activity' such as tennis,
football, baseball etc.

"Sports" would refer to more than one 'phyical activity'

"I play sports"="I play basketball, golf, and football."
"I play a sport"="I play water polo."

Besides grammer this is no big difference between these two words.

There is not really a diffrence between the word sport and sports
except for the fact that sports is usually used to refer to many
sports, like in the news they will refer to all sporting events that
day if they say sports. but if you say I play this sport than it only
refers to one sport instead of a grouping of them