This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
詍 combines 言 (speech) with 世, but the exact historical development and original meaning are uncertain.
The left side is 言 (speech) and the right side is 世 (world). Picture words spreading through the world, but remember the meaning is uncertain.
For エイ, imagine an ancient word echoing through the world: the echo sounds like 'A' (エイ), but the meaning remains a mystery.