Thing entered in a PDA, say

• Cal. entry
• Meeting with an atty
• Calendar entry (Abbr.)
• Prearranged mtg
• Sched. entry
• Something scheduled by a secy
• Abbr. in an organizer
• PDA entry
• Date with a D.D.S., e.g.

Wiktionary Word definitions in Wiktionary
n. (abbreviation of appointment English)