Should “round” only be used to describe 2-d objects?

My high school teacher used to say, "No, the world is not round it is globular". Strictly speaking, is round more appropriately used to describe 2-dimensional objects (circle, oval, tire, plate or saucer) and globular, spherical or even cylindrical better for 3-dimensional objects (ball, egg, tube, pint glass or the earth). Or are we just dealing with a persnickety high school teacher?

Persnickety. Round is commonly used to describe spherical objects:

http://en.wiktionary.org/wiki/round

2 . Spherical; shaped like a ball; having a circular cross-section in more than one direction.

http://dictionary.reference.com/browse/round

19 . any round shape, as a circle, ring or sphere.

http://www.thefreedictionary.com/round

1 . a. Being such that every part of the surface or the circumference is equidistant from the center: a round ball.

Merriam-Webster defines round as:

having every part of the surface or circumference equidistant from the center

It sounds to me like a sphere would fit that definition nicely.

It's possible that math or geometry specialists might define round as only applying to two-dimensional objects, but that usage would be properly considered jargon, rather than common English.