lenticular galaxy

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A galaxy having a central bulge surrounded by a flattened disk that contains numerous stars but relatively little interstellar matter, creating a conspicuous pattern of spiral arms.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun astronomy A galaxy that like spiral galaxies has a flat disk but unlike them has lost most of its interstellar matter and therefore has no spirals; considered a transitional form between spirals and elliptical galaxies.