I've hesitated posting about first words for a few weeks now. Alisa has occasionally used a verbal expression purposefully; but, their usage was right on the edge of being actual words. Now I can say without doubt that Alisa is using words, or at least verbal approximations of words.
In order, her "words" are:
"Da" - Used when pulling out any one of a series of three Japanese children books. The main character is a bright red fellow named だるまさん ("Darumasan"). Although she says "Da" many other times, this one has a particular inflection that is not used elsewhere. She's been saying this for about three weeks now; but, since its really such a simple syllable that is also used so many other times, I've hesitated really calling it word usage.
"Te" - This is really 手, the Japanese word for 'hand'. Its used on a particular page in the Darumasan trilogy where the main character shows his hands. She's been saying this for about two weeks; but, only recently started repeating it when we show our own hands.
"Uh Oh" - This is the classic two-syllable response for when something goes wrong. She first started imitating us with this saying about two weeks ago; but, only in the last few days has she really taken to the expression. Whenever she drops something, most commonly from her diaper changing table or when she's being carried by arm, she exclaims "Uh oh!" Being her only English expression thus far, I find it particularly endearing.
Update: In case you're wondering about Leia, she's not yet started talking. She makes plenty of different noises and syllables; but, so far there's no detectable word usage per se. She is much further ahead in walking, though. It takes her no time to jump up (by holding on to my hand) and start cruising across the room. She's definitely more physical, though smaller, than Alisa.