zine
zip codes
U.S. zip+4 codes are listed online at www.usps.com/zip4/. To speed delivery of mail to U.S. addresses, use zip+4 codes.
zone of proximal development = ZPD (associated with L. Vygotsky. Note change in capitalization of this term.)
ZPD = zone of proximal development (associated with L. Vygotsky. Note change in capitalization of this term.)