"To send a reply" means to respond to a message or question that someone has sent to you.
Sentences with «to send a reply»
You should keep the copy of the letter and send your reply by certified email. (personalmoneyservice.com)
I was really impressed so I sent him an email invitation to check out my profile and send a reply message if he was interested. (blackchristianpeoplemeet.com)
Send in your request, question or describe your dog's health care issue and we will do our best to send a reply with helpful advice. (dog-health-handbook.com)