botanical gardens, arboretums, nature centers, conservatories, historic sites, archeological sites, and monuments; (C) Plant, tree and flower nurseries ; (D) Public utility rights-of-way and similar public works compatible with the purposes of the POS zone; (E) Lighting of any congregate
Read it in the chapter →How this ordinance defines it
The operative definition is the local one. Codes routinely subdivide a category into tiers — “day care 2, family”, “group home 2” — and attach different permissions to each, so only Alexandria’s own text settles what this covers.