If you want to use Terrell in a Spanish context, you could simply use the name as it is.
For example:
* "Terrell es mi amigo." (Terrell is my friend.)
* "El Sr. Terrell es un buen maestro." (Mr. Terrell is a good teacher.)
If you need to find a Spanish name that is similar in meaning or sound, you could consider names like:
* "Teodoro" - meaning "gift of God"
* "Terencio" - a Latin name that sounds similar
* "Fernando" - another popular Spanish name
It depends on the context and what you are trying to achieve.