Here is a well organized post providing abbreviations and terminology so that any one, android master or newb, can have a quick reference guide to all things android.
adb: Android Debug Bridge, a versatile tool lets you manage the state of an emulator instance or Android-powered device
ADK: Android Development Kit, What people use to develop anything for the droid such as ROM's
Baseband: In communications and signal processing, the baseband describes signals and systems whose range of the frequencies measured from close to 0 hertz to a cut-off frequency, a maximum bandwidth or highest signal frequency; it is sometimes used to describe frequencies starting close to zero
Boot Loader: State in which the droid can be flashed from RSD with an appropriate .sdk file that reprograms the phone into a specific ROM or update. This is typically a last resort when the recovery screen cannot be reached to make a much simpler and less risky solution
Boot Loop: simply means something is preventing the phone from completing it's boot cycle and is stuck between the boot animation and the unlock screen, creating a looped animation. This is often fixed by either reloading a Nandroid, or Reflashing a rom from the Boot Loader.
Brick or Bricked: Jargon for a completely unrecoverable device, (no more than a brick or paperweight)
Bug or Software Bug: an Error or flaw in software that produces a failure or unexpected/unwanted result. Typically created from incorrect code, this is why some ROMs are better and smoother running than others because certain developers have taken the time to input "perfect" code
Busybox: BusyBox is a single multicall binary that packages the functionality of most widely used standard Unix tools, BusyBox provides a fairly complete environment for any small or embedded system.
ClockworkMod: A recovery program that is often used to apply updates, ROMs, or create a back up or restore a backup file
De-odex: Apk files have respective odexes that devs use to supposedly save space. Deodexing means you convert it back to a .dex file and put it back inside the apk. This allows you to easily replace files (not having to worry about odexes), but the main point was to deodex services.jar so that you can change all text to different colors (such as the clock color to white) and to deodex services.jar, you need to deodex everything.
Dev. or Developer: An individual that creates, or alters a file in such a manner as to advance the program
Flash or Flash Memory: a program technology that can be electrically erased and reprogrammed
Kernel: The governor of the CPU usage and Battery output, one can upload certain Kernels to achieve greater performance speed of their device at the cost of some battery life
Nandroid or Nandroid Backup: A file typically created in the custom recovery program, such as SPRecovery, that is a carbon copy of whatever state your phone is in before a drastic change is made. the file then can be moved onto or off of the SD card for later use in case something should go wrong in the ROM or Update, or a Boot Loop occurs
OS: Operating system, I.E. Windows Vista or MAC or ANDROID
Overclocking: Speeding up the CPU past the factory presets to achieve a faster and more responsive device
ROM: Read Only Memory, a program used to make changes to anything from the look of the home screen, to icons to custom boot animation
Root: Common word associated with giving a user "super user" access to their phones programming and other various aspects that would normally not be possible, also known as "Jailbroken" for iPhone's
Shell or SSH: secure shell or ssh is a network protocol that allows data to be exchanged using a secure channel between two networked devices
Stock: Simply means an unaltered state, such as when you first purchase your phone from Verizon, or when you do a factory reset. Current stock image is Android 2.2 (Froyo)
SU: "Super user", or root permissions
Theme: A set of icons, backgrounds and app trays that change the ascthetics of the overall look of the droid and its applications
TUN/TAP: Refers to a network Tunnel, operates within layer 3 packets, or ip packets. Packets sent by a system via a TUN/TAP device are delivered to a user-space program that attaches itself to the device. A user space program may also pass packets into a TUN/TAP device. In this case TUN/TAP device delivers (or "injects") these packets to the operating system's network stack thus emulating their reception from an external source.
Underclocking: Slowing down the CPU mainly to limit battery usage
.apk or APK's: An .apk file extension denotes an Android Package (APK) file, an .apk file can be opened and inspected using common archive tools
.tar: Similar to a zip file, a tar file archives multiple files into one file
.tgz: TGZ files are commonly used as install packages for Slackware Linux.
.zip: Zipped file used to archive multiple files into one to save space and allow for single download Linux.
[Credit to Sam Fisher on DroidForums for this list]