do·er 
(dər)
(dər)n.
1. One who does something: a doer of evil deeds.
2. A particularly active, energetic person: a real doer in party politics.
- alpha decay
- alpha error
- alpha-fetoprotein
- alpha globulin
- alpha-helical
- alpha helix
- alpha-hydroxy acid
- alpha interferon
- alphameric
- alphanumeric
- alphanumerical
- alphanumerically
- alpha particle
- alpha privative
- alpha ray
- alpha-receptor
- alpha-synuclein
- alpha-tocopherol
- alpha wave
- Alpheus
- Alphonse
- Alphonse
- Alphonse
- Alphonse Marie Louis de Prat de
- alphorn