IPA: /ˈiːmeɪlər/
KK: /ˈiːmeɪlər/
A person or thing that sends an email.
As an emailer, she frequently communicates with her clients online.
Emailer → It is formed from "email" (a blend of "electronic" and "mail", meaning messages sent electronically) and "-er" (meaning a person who). An emailer is a person who sends electronic mail.
Think of someone who sends messages electronically — that's what an emailer does.