Belfast·SPG003 Residential Design·Page 107
Houses in Multiple Occupation (HMO)
A HMO is a property rented out by at least three people who are not from the same household but share facilities like the bathroom and kitchen.
A house in multiple occupation is a property rented out by at least three people who are not from 1 household (e.g. a family) but share facilities like the bathroom and kitchen.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/belfast/SPG003 Residential Design.pdf