(paleontology, geology) Initialism of Carnian pluvial episode.

(education) Abbreviation of Certificate of Proficiency in English. (the highest-level ESOL exam awarded by Cambridge University) / (engineering) Abbreviation of chartered professional engineer.

(computing) Initialism of Content Protection for Recordable Media. / (politics) Initialism of Communist Party of Revolutionary Marxists.

(UK) Initialism of community psychiatric nurse.

plural of CPN

(US) Initialism of Corporation for Public Broadcasting. / (UK politics) Initialism of Communist Party of Britain.

(initialism, American Association of Attorney-Certified Public Accountants)

(geometry) Initialism of corresponding parts of congruent triangles are congruent, a theorem regarding congruent triangles, stating that if two or more triangles are proven congruent by any method, then all of their corresponding angles and sides are congruent as well.

(geometry) Initialism of corresponding parts of congruent forms are congruent.

(Earth science, UK) Initialism of Centre for Polar Observation and Modelling. (centre for research into polar region processes)