Typically, a Single Purpose Entity (SPE in conventional jargon) is an LLC used for one purpose. SPE's are also referred to as single-asset or special purpose entities. They are a legal entity created to satisfy a narrow, specific, or temporary purpose.
SPE's are typically used to isolate liability between companies and among other assets.
I teach real estate investors to put each piece of real estate they buy into individual Land Trusts. Therefore, each Land Trust is an SPE.
Some of my students (especially in California) have trouble with title companies, closing agents, and attorneys who have mental issues with the words "Land Trust." Here's a possible solution for them. I suggest that they start using the term "SPE" in place of "Land Trust."
From the beginning of your conversation with these closing actors, do not say you are using a "Land Trust." Tell them you are using a "Single Purpose Trust." Or, you could also refer to them as "Single Purpose Business Entities."
What you call them really does not matter. The players are controlled by what is in the Trust Agreement.