Aridai

The name Aridai is probably Persian and shouldn't be expected to mean anything in Hebrew. BDB Theological Dictionary suggests that our name may "perhaps" be a transliteration of the known Persian name Haridayas, which means Delight Of Hari, but also declares the text "very uncertain". Alfred Jones (Dictionary of Old Testament Proper Names) suggests our name to mean Magnus, Preaclarus (Great, Excellent), but also forwards a possible relationship with the Persian name Airyadao, meaning Digna, Dans (Worthy, Giving) or even Aryaday, which means Donum Ariae (Gift Of Ari)
A Hebrew audience, on the other hand, might have linked the name Aridai to a cluster of names that modern scholars find difficult to explain, and which may have to do with the root ערד (allowing the letter א to alternate with the ע, which sometimes happens);
ערד
The verb ערד ('arad) doesn't exist in extant Biblical texts but in cognate languages it means to flee or be free. A derived noun, ערוד ('arod), refers to the wild ass, and does occur in the Bible.

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רוד
Verb רוד (rud) means to wander or roam restlessly. Noun מרוד (marod) means restlessness or homelessness.

In Hebrew this name means My Freedom or free enough. With the etymology; From (1) the verb ערד ('arad), to flee or be free, and possibly (2) the particle די (day), sufficient or enough.
Some related names are; • Via ערד ('arad): Arad, Ard, Ardon, Aridatha, Arod, Arvad, Herod, Herodion, Irad
• Via די (day): Bedeiah, Dizahab, Madai, Shaddai.