Return on Investment 
region of interest 
ROILINE 
Region of Influence 
reactive oxygen intermediate 
regions of interest 
Replacement of Obsolete Items 
Report of Incidents 
Report of Investigation 
Republic of Ireland 
return on investments 
rules of interaction 
Avior Airlines 
radical oxygen intermediates 
radiological operating instructions 
Radius of Influence 
Rampant Overhead Investment 
Range Operations Instruction 
Rate On Investment 
reactive intermediates of oxygen 
reactive oxygen intermediates 
reactive oxygen species 
Realizations Of Impropriety 
Really Old Ideas 
Really Old Idiots 
Really Old Interfaces 
Really Old Inventory 
Reap Our Income 
Reasonable Operator Initiative 
Recognition Of Irony