Define "Due"

Guess what everyone! Amy is officially 40 weeks today! That's right, today is our technical "due date". So, um, what's that supposed to REALLY mean? I mean, our little boy hasn't shown any signs of wanting to come out yet. Amy hasn't felt any contractions or other indications of impending labor. In fact, the teacher of our childbirth classes said the average first time pregnancy without intervention (induction, c-section, etc) runs around 41.5 weeks. So what's all the fuss about a due date?!

Amy and I are planning to go to the park tonight with Sydney and enjoy the outdoors if possible. Amy has been gardening and we've been going through all of the Spring routines like the first mowing, feeding the lawn, weeding, etc. Naturally I have kept Amy from doing anything that might overdo it, and we have recruited family members to help with some things, but I think the rest of the family is on pins and needles more than we are. We get a number of calls each day asking how things are (as if we wouldn't call our family members to let them know... ;-) But I'm sure that's just natural excitement, and I appreciate the care and concern. Basically, we're just hanging out and waiting. The overnight bags are packed for the hospital, the arrangements are made, now we just wait. Which brings me back to my question - why do they call it a "Due Date?" Can my bills be "due" like this? I'll call the mortgage company and tell them "Yeah, my payment should be there sometime this month. It could be this week, could be next..." Not sure they'd go for that...

So perhaps there's a better term to use. Maybe "Arbitrarily Chosen With No Input From Your Child Date?"

Suggestions?