This has happened to me a few times.
I used to hear my nan call me, as she did when I had to get up for school. Like most kids I would give it another 5 minutes and go back to sleep till she used to stomp up the stairs and yell at me at point blank range. Sometimes I would hear her call me, I would shout "Ok!" and then she would shout again and I would shout back again as if she didn't hear me. When I came downstairs and told her I heard her the first time, she would tell me she hadn't called me
I've heard my partner talk to me on a couple of occasions. I heard him say "I need money" and another time "What's the number?" If he goes to the shops I usually give him money from my purse as he doesn't really carry any but I don't know what the number thing could be about. Both times I heard it realy clearly and these have both been recently but he was at work both times. I have had to check my phone to make sure I have hung up properly and I looked round the house to make sure he hadn't come home and I hadn't heard him come in. He does that someimes and then scares the carp out of me when I walk into the kitchen and he's just standing there. Also, I stepped off a plane in 2002 I have had a problem with my left ear meaning I can only hear about 50% from it.
I don't know what it could have been and I still can't explain it. Perhaps it was my mind playing tricks, but to hear it that clearly still makes me wonder.
Perhaps your wife has been thinking about you and subconsciously heard you say something. I think that is what I would put my experience down to.
Unless you live with 4 African Grey Parrots, like my mum, and you walk in and they start having a conversation between themselves in my mums and sisters voice.... One has my stepfathers, smokers cough, and one talks as if he's on the phone. That is a bit scary when I let myself in and there is no one home