Don't be afraid to use "trepid." After all, it has been in the English language for more than 350 years - longer, by 30 years, than its antonym "intrepid." "Trepid" (from Latin trepidus, meaning "alarmed" or "agitated") isn't used as much as "intrepid," but it can be a good word at times. Bill Kaufman, for example, found a use for it in a May 7, 2000 Newsday article, in which an aquarium volunteer is "asked if she is perhaps a little trepid about swimming with sharks in a 12-foot deep, 120,000 gallon tank." (Her fearless reply: "Not really.") The more intrepid among you might even consider using "trepidate" for "to tremble with fear" and trepidant, meaning "timid" or "trembling." These are uncommon words, granted, but they haven't breathed their last.