Darby's most used word is "hi". I like to say its her FIRST word (my first word was "hi") but she did say "elmo" before that. Although she doesn't say "elmo" half as much as she says "hi"! Therefore, I say "hi" really IS her first word! She also says "uh-oh", if that's considered a word!
Here's a video of D saying "hi" and waving from her packnplay. She is SO on the go, putting her in her packnplay is a must for my sanity. I can only say "Darby, no!" so many times a day!