I encountered different hints at origin when I looked up “wraith” in my Webster’s Unabridged (1979) and on the Internet.

I googled the word and peeked at the first four definitional sites, and all of them said “origin unknown.” They agreed it came from Scotland and at least two of them cited first use in 1513, in a translation of the Aeneid by one Alexander Douglas. I read that J.R.R. Tolkien thought wraith was connected to writhe (from the Middle English writhen, which meant twist, turn).

My print dictionary declares that wraith is from the earlier Scottish warth (guardian (angel)) which came to us from the Old Norse vörthr (warden, guardian).

All references seem to agree that wraith means an apparition that’s an exact likeness of someone, usually seen just before that someone’s death. Other meanings are ghost or specter, any insubstantial form or semblance, and even a barely visible vaporous column.

I think I had every meaning in mind except the first, when I named this sonnet.

I dwelt eleven seconds in your mind
today: six moments now, five instants then.
For fractions of eternity I shined
into idea in you. I flashed again
and flickered out before you caught my form,
but I was there and radiant as youth.
Disembodied I in you grew warm
eleven seconds, glowing like the truth.

My pulse insists upon a simple goal:
I’m dancing deep for wisdom as I dream
the chair at God’s right hand, where I am taught
the answers to the question, how the whole
is crazy fabric, and the strongest seem
is simile, like me inside your thought.