CIDR may refer to:
Classless Inter-Domain Routing, a way of interpreting IP addresses
CIDR-FM, an FM radio station in Windsor, OntarioControlled Internal Drug Release, an intravaginal drug delivery system used to control the oestrus cycle in cattle, sheep and goatsConference on Innovative Data Systems Research
See more at Wikipedia.org...
CLASSLESS INTER-DOMAIN ROUTING. CIDR