Iontrálacha san Fhoclóir Nua Béarla-Gaeilge a bhrabhsáil
- organising
- organising principle
- organism
- organist
- organophosphate
- orgasm
- orgasmic
- orgy
- orient
- oriental
- orientation
- oriented
- orienteering
- orifice
- origami
- origin
- original
- original print
- original sin
- originality
- originally
- originate
- origination
- originator
- oriole
- ornament
- ornamental
- ornamentation
- ornamented
- ornate
- ornately
- ornithological
- ornithologist
- ornithology
- orphan
- orphan drug
- orphanage
- orthodontic
- orthodontics
- orthodontist
- orthodox
- orthodoxy
- orthogonal
- orthographic
- orthography
- orthopaedic
- orthopaedics
- orthopaedist
- oryx
- oscillate