When you are shopping for a camera lens, it almost certainly has a series of strange abbreviations on the lens along with any advertisements. Chances are that you are at least somewhat familiar with these abbreviations if you are purchasing a lens of the same model as your camera. Many of these cryptic abbreviations often deal with controlling lens vibration, chromatic and spherical aberration, whether the lens is macro capable, the quality of the lens and housing etc..
Keep in mind that each manufacturer may go through a different path for a certain feature. For example, how Nikon may control dispersion may vary from how Canon controls dispersion in its lenses. Also, when comparing lenses, simply because a lens advertisement may not directly state that a lens has a specific quality, it does not necessarily mean that the lens lacks that feature. In fact, all lenses in a particular line may have a specific feature such as a low dispersion coating.
I have included 3 third party vendors below with a listing of common abbreviations used on their lenses. In some cases lenses from third parties may produce excellent results at a value price.
Here is also a link that does a great job when comparing camera lenses.
ASP: Aspherical lens (reduced number of components and smaller size)
APO: Low dispersion glass to control chromatic aberration
OS: Optical stabilization
HSM: Hypersonic Motor (A very quiet fast focus)
RF: Rear focus (Moves the rear elements for faster focus)
IF: Inner focus (Internal elements charge without changing lens length)
A: Art Series
CONV: teleconverter compatible
EX: Professional body finishing
DG: Full frame cameras
DC: Crop frame cameras
DN: Mirrorless cameras
SP: Superior Performance (superior sharpness and contrast)
LD: Low dispersion elements
IF : Internal focusing (lens length does not change)
AD: Anomalous Dispersion (Controls chromatic aberration)
ASL: ASpherical Lens (hybrid lens that controls for spherical aberration and chromatic aberration with fewer lens elements)
LAH: LD Aspherical Hybrid: (Another hybrid lens that controls dispersion)
XR: Extra Refractive Index: (Allows wide angle and wide angle zooms to have smaller front elements)
ZL: Zoom Lock (Keeps zoom lens from shifting when pointed down)
VC: Vibration compensated
Di: Digitally integrated