bik·er 
(bīkər)
(bīkər)n.
1. One who rides a bicycle or a motorbike.
2. A motorcyclist, especially a member of a motorcycle gang.
- dispraiser
- dispraisingly
- disprize
- disproof
- disproportion
- disproportional
- disproportionally
- disproportionate
- disproportionately
- disproportionateness
- disprovable
- disproval
- disprove
- disputability
- disputable
- disputably
- disputant
- disputation
- disputatious
- disputatiously
- disputatiousness
- dispute
- disputer
- disqualification
- disqualify