- optative
- object
- oblique
- occlusive
- oration
- orinasal
- orthoepic
- orthoepist
- orthoepy
- oxymoron
- oxyton
- palatal
- palatalize
- palilogy
- palatalization
- palatogram
- paradigm
- paragoge
- paralipsis
- parallelism
- parasynthetic
- paratactic
- parataxis
- parathesis
- paronym
- paroxytone
- part
- participial
- participle
- particle
- partitive
- passive
- past
- pedigree
- penult
- penultimate
- perfective
- pendent
- perfect
- period
- phoneme
- phonologic
- phonology
- phone
- phonemic
- phonological
- plural
- pluperfect
- plosive
- positive
- possessive
- postpositional
- potential
- polysemous
- postpositive
- postfix
- postposition
- praxis
- precative
- precatory
- preconsonantal
- predeterminer
- predicate
- predication
- predicative
- prefix
- preposition
- prepositive
- pretonic
- prevocalic
- present
- preterite
- primary
- principal
- proclitic
- preterit
- pretone
- primitive
- privative
- prodelision
- prolative
- pronoun
- proparoxytone
- protatic
- progressive
- pronominal
- proper
- prosthesis
- protasis
- protases
- prothesis
- pure
- purism
- purist
- puristical
- quadrisyllable
- qualify
- puristic
- quadrisyllabic
- qualyfier