If CURLOPT_SSL_VERIFYPEER is false, is the data transfer no longer secure?

I've recently run into a problem posting data to a server whose SSL certificate was updated. I did some research and I found that when CURLOPT_SSL_VERIFYPEER is set to false, post date goes through successfully. Can somebody explain the relationship between CURLOPT_SSL_VERIFYPEER and _VERIFYHOST? Also, if I set VERIFYPEER to false, am I no longer transmitting the data over a secure connection?

Thanks a ton for any help anyone can give.