Maybe losing confidence in a buzzword has less to do with the number of times it's used, and more with the number of times it's used incorrectly. Nothing makes me cringe more than hearing a term like "brand" used to mean everything from logo design to a new advertising campaign. A brand is not tangible, it lives in the heads and hearts of consumers. You can't spray-mount it to something.
When we use jargon interchangeably, with little regard to the original meaning, we commoditize our words and make what we say worth nothing. That hurts everyone. There's enough of a negative perception out there among CMOs that agencies provide little value or relevancy without having us propagate it further. Being able to call your small agency "strategic" versus "executional" takes more than just throwing a few buzzwords around.
Just look at the word "strategic." Have you met anyone in the last five years who didn't describe his marketing plan as strategic? Like many organizational terms, strategic was borrowed from the military and it means to have an impact on units outside of your division, i.e. considering the bigger picture. In business, the term strategic is used to describe a long-term initiative, one that's not just tactical, one that affects the entire organization. (Spending more than five minutes thinking about an idea does not make it strategic.)
Another term that has fallen victim to word-tedium is "public relations." Nothing makes our PR people groan more than to hear account managers or clients refer to public relations as "free" or just "being nice to customers." Creating a dialogue with consumers isn't just "nice," it's necessary to understanding their needs and endearing them to your brand. And although scoring earned media is a budget-savior and an awesome way to create impressions, it's not easy, nor is it "free."
Don't be embarrassed to check a term before using it; there are media and theories introduced every day, so you're bound to miss a few. I know I certainly do. I checked out some of the online ad-term glossaries wondering if they could be a resource, but most only listed basic vocab like "insertion order."
Best advice I can give is to visit Amazon.com and buy a few books by authors who've done their research and that speak to your favorite component of marketing, whether it's brand building or public relations, and study them. Because borrowing a few fabulous words from someone in-the-know isn't half as bad as making stuff up.