R.T.S. TERMS TO MAKE YOU SOUND SMART WITHOUT ACTUALLY KNOWING THE GAME:
Metagame: Once a term for the dynamic that arose outside of the game itself based on the tendencies of players to adapt to trends and common counters, this term is now a meaningless, pseudo-intellectual way to say "game."
FE: The common acronym for Fast Expand or Fast Expansion. Just because you say you "throw down an FE" does not make you Flash (EffOrt?).
Timing Push: A timing push is a concept based around a window in the metagame (see that?) wherein your opponent has few units or the wrong type of units. For example, when your opponent expands he invests money in his economy, creating a point in time when he has fewer units and is vulnerable to a timing push. Also, when one player makes a tech switch this also creates a window of opportunity until his or her opponent can switch accordingly. So when you sit contentedly making units from one base of resources and move out arbitrarily to stomp your silver level opponent because you like the size of your army and you finally figured out how to build a Raven this is not a timing push. SCOUT TO DISCOVER TIMING WINDOWS.
Dual: Not a big deal, but there are some of us out there who would rather you just say "two."
Viable: Viability is not binary. Take that statement to heart and carry it with you all the way to gold league. Yes, it's true that some strategies or tactics are more difficult to implement or easier to counter for your opponent, but sometimes those are the most rewarding. It behooves the Beta tester to find creative new ways around obstacles in the metagame (BOOM! Two for two!) rather than declaring seemingly difficult things unviable. Try this: Pick a unit and find a use for it instead of picking a use and finding a unit for it. This segues nicely into:
Imbalanced: Imba, OP, overpowered, broken, whatever you want to call it. Yes, it is a Beta and there may be some balance issues. But who will emerge the stronger, more versatile player: The player who declares imbalance at the roadblocks in his/her play and is at the mercy of Blizzard's buffs and nerfs like a begging puppy, or the player who is determined to win regardless of balance issues and is that much stronger when the buffs come? AND MORE IMPORTANTLY, very few players are good enough at Starcraft II for racial balance to even matter. If you have 3,000 minerals in the bank, expand at ten minutes, and think that "micro" is A-moving banelings (hint: they often do better right-click moved through the enemy), then there are much greater things to worry about than the range of a voidray you lost to that one time you almost got to top ten in gold.
Micro/Macro: These two myriad terms are perhaps responsible for more ambiguity than any others over the years of Starcraft glory. Saying that you have good micro and bad macro (hint: that's what all new players say) means next to nothing. Saying that you have trouble knowing when to expand, trouble controlling large army groups, or trouble saturating new bases with workers is... what's the word... USEFUL. The quality of the advice you receive is directly proportional (think x=y) to the quality of your request for it.
BY REQUEST
Cheese: A few weeks back there was actually a great post concerning the definitions of the overused terms "cheese" and "all-in" by a well known user whose name escapes me right now, so credit is due to him for these definitions. Cheese is a strategy whose success is very dependent on remaining unknown to the enemy. This means that something like a Dark Templar rush is often considered cheese because a player aware of this plan can prepare detection ahead of time, while something like Hellion harass is less cheesy because you can be fully aware of the impending Hellions and still take damage without taking measured precautions (like blocking your ramp, making a spine crawler, or running drones). NOT ALL CHEESE IS ALL-IN.
All-in: All-in is a word commonly used to describe a strategy you have been beaten by. For example: "That noob went all-in 2-Gate FE!!!!!!!111!!!zomg!!protossisOPnerfmoar!!!" All-in is the perfect scapegoat! You can never have a bad game again with the handy all-in accusation! In normal person land, all-in describes a strategy that aims to end the game at one specific point and often lacks a STABLE followup. The perfect example is the 6-Pool, a build whose low drone count is crippling to the production of anything more than handfuls of zerglings. Yes, there may be a followup, but between players of equal skill levels and equal numbers of arms a failed all-in is a failed game. Keep in mind that by definition an all-in can occur in the late-game.
Realistically, good players can recognize a self-improvement thread over a look-I-learn-these-word-now-I-can-sound-like-SC2-playur attention-grabbers. So before you make that thread, stop and think: How can I purposefully avoid the buzzwords, be taken seriously, and get responses from people who are not my own level with similar problems? Good luck and have fun out there guys.
P.S. Metagame metagame metagame.