Ortho-Para Director Definition:
A group that directs the regiochemistry of an electrophilic aromatic substitution reaction such that the incoming electrophile is installed at the ortho or para positions.
Ortho-Para Director Explained:
In electrophilic substitution the substituents that allow electrophilic attack of ortho and pera to a substituent. Ortho/pera directors are activators except for halogens which the opposite.