Microorganism/microorganisms - apart from the fact it has two Os in it, with my speech issues I pronounce this micro-orga-NIZ-UMS. I like it. I describe lots of things as organisms, including other humans / animals / whathaveyou. Hi - good all purpose word, easy to say, tends to break the proverbial ice and convince people you might not be that weird, generally polite and cheerful.
For some reason the word Smite always cracked me up. I like the feel of saying the word Spline. I also enjoy Pernicious, Conniving, Vigilante (because of a short on Sesame Street), and anodyne.