Aleithia is a variant of Alethea, from Greek meaning 'truth' or 'sincerity.'
Aleithia is another variant of Alethea, and it keeps the Greek root aletheia in view, with its meaning of truth or sincerity. The spelling adds a little extra length and glow, but the underlying idea is still clear: a name built around honesty, clarity, and what is fully revealed.
That gives Aleithia a bright, virtue-driven center. In modern use, it feels more ornate than Alethea and slightly more romantic than Aleitha, which may be why it works so well as a contemporary elaboration. The name has the kind of structure that sounds classical even when it is newly coined or newly shaped. Aleithia carries an impression of openness and integrity, with a softer finish that makes the ancient virtue feel wearable today.