Alkidemos, meaning “defender of the people”, was used by Livy to describe the version of Athena worshipped primarily in Macedonia. She was usually depicted with a thunderbolt and aegis.
The passage was (42.51):
This council was held at Pella, the capital of Macedonia. “Let us then,” said Perseus, “wage war with the help of the gods, since thus you decide.” Written orders were despatched to all his generals and he assembled the whole of his forces at Citium, a town in Macedonia. After sacrificing in regal style one hundred victims to Minerva, whom they call Alcidemos, he set out for Citium, accompanied by a number of court nobles and his bodyguard.