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(colloquial) Initialism of pretty damned/darn quick: very quickly, as quickly as possible.

(electronics) Initialism of personal digital assistant. / (colloquial) Initialism of public display of affection. / (computing theory) Initialism of pushdown automaton.

Initialism of Pacific Daylight Time.

Initialism of Physicians' Desk Reference.

Initialism of preliminary design review.

(communication, electronics) Initialism of High Speed Physical Downlink Shared Channel (in UMTS).

Initialism of pre-delivery inspection. / Initialism of polydispersity index. / (automotive) Initialism of petrol direct injection. (fuel injection)

Initialism of Product Data Management. / (signal processing) Initialism of pulse-duration modulation. / (signal processing) Initialism of pulse-density modulation.

Initialism of power distribution unit. / Initialism of propwash deflection unit. / Initialism of professional development unit. / Initialism of protocol data unit. / Initialism of poor dumb user.