AF-s - Focuses silently and has instant manual override just by grabbing the focus ring.
AF-I (AF-Internal Motor): 1992. All AF-I lenses are AF and AI-S
AI - Aperture Indexing: AI-E 1979, AI-S 1982, and AI-P 1988 which has a built-in CPU
Aspherical lens element
Virtually eliminates coma and other types of lens aberration, further improving image integrity.
D - (1992) Tells your camera's meter the distance to your subject. This helps a little for flash exposure metering.
DX - Only works on digital cameras. The corners will be black at many focal lengths on a film camera.
ED - Extra-low Dispersion (ED) glass element minimizes chromatic
aberration.
FX - FX-format CMOS sensor, full FX resolution
G - No aperture ring - G-type DX NIKKOR is designed exclusively for use with
Nikon digital SLR models.
IF - Internal Focusing. The lens focuses with only the slight motion of a few internal elements instead of having to crank the entire lens in and out. This means the front no longer rotates as you focus, making polarizing and grad filter use easy.
M/A (Manual/Automatic) mode - Even while in autofocus you may simply grab the focus ring to make manual focus adjustments. Next time you tap the shutter it returns to AF mode, and next time you grab the ring you're instantly in manual mode. I wish everything on earth worked this well.
RF - Rear Focusing, the lens achieves focusing by moving the rear elements; similar to IF
SIC - Nikon's latest multicoating to increase light transmission and reduce ghosts.
SWM - Silent Wave Motor, which is an ultrasonic piezo device similar to Canon's USM. It moves things without making noise. The lens focuses silently, handy for snoop photography and for sensitive pets and wildlife.
VR II system offers the equivalent of using a shutter speed 4 stops faster