Many people, including yours truly, enjoy displaying word power by using a 25 cent word word when a single syllable word would do. Some words just sound good and we represent ourselves with our choices of words, but, sometimes, this principle of using big words where little ones will do is just plain stupid. Many jail-house "scholars," low-end storefront preachers, and uneducated celebrities seem to enjoy using words with just one syllable too many. They use these words when clear alternatives that are less of a mouth full are obvious.
The offenders: 1 Resiliency: If you're talking about the quality of people, creatures, or "whatevers" to keep going no matter what kind of injury they've suffered, then why not just use the word Resilience? Both words mean exactly the same thing.
2 Relevancy: This word shouldn't even be used by prison lawyers standing before judges. "Yo' Honor, I maintain my previous murders have no relevancy....naw that's stupid, relevance..." Again, there is no difference in meaning between this word and its fraternal twin, Relevance.
3 Economical : Before you word enthusiasts attempt to poke my eye with your index finger, I need to state that I am aware that these words, which are both adjective variations on the nouns economics or economy, carry different connotations. Economical often means "thrifty" or "efficient." Economic simply refers to the the financial workings of the world. Nonetheless, many fail to make the distinction, so we see word abominations like "economical factors."
4 Irregardless: This word is just stupid. If you mean to say "not regarding," then pray tell me what exactly is wrong with "regardless"? This is the kind of word your redneck co-worker who was listening to Rush and now wants to share the conservative gospel with you uses, " Rush says irregardless of how much plutonium we release into the atmosphere, we couldn't possibly, blah, blah, blah,."
Avoid the false sense of word power that comes with unnecessary syllable and a stupid word.