1. Iasón and Iasan are Irish Gaelic forms of Jason [q.v.].

2. This form is also Greek, meaning "a healer".

3. Iason was the Medieval English written form of Jason.

• A correspondent [LA] has pointed out that many [?most] earlier manuscripts used a common script for capitals "I" & "J". Thus Jason may have been written and then transcribed as Iason. Many on-line services have transcribed original documents faithfully so this version might be the one to look for in the indexes to earlier records.