mail·er 
(mālər)
(mālər)n.
1. One that uses the mails: large commercial mailers.
2. One who addresses, stamps, or otherwise prepares mail.
3. A container, such as a cardboard tube, used to hold material to be mailed: a cardboard book mailer.
4. An advertising leaflet included with a letter.
- heterochronic
- heterochronous
- heterochrony
- heterocycle
- heterocyclic
- heterocyst
- heterodactyl
- heterodactylous
- heterodactyly
- heterodox
- heterodoxy
- heterodyne
- heteroecious
- heteroecism
- heterogamete
- heterogametic
- heterogamic
- heterogamous
- heterogamy
- heterogeneity
- heterogeneous
- heterogeneously
- heterogeneousness
- heterogenic
- heterogenous