Sorry in advance for the stupid question.

Consumer purpose loan secured by vacant land that has no prior liens on it. Customer is taking equity out of the land to pay off credit cards. Under the TRID rules, the purpose stated on the Loan Estimate/Closing Disclosure is "Home Equity"; even though, there is no home involved.

I told my boss that and he thinks that I missed something in the regulation...

Either something the CFPB didn't anticipate, or a road they didn't want to go down i guess....but i'm with you......seems like "Home Equity" is your only choice. Purchase, refinance, nor construction work for the purpose, so that seems to be all you're left with.

This is from 1026.37(a)(9) and tells you how purpose must be completed:

Purpose. Applicant's intended use for the loan, using one of the following:
(i) Purchase. If to purchase property identified in 1026.37(a)(6);
(ii) Refinance. If not for “Purchase”, and if refinancing an existing obligation that is secured by
property identified in 1026.37(a)(6);
(iii) Construction. If not for “Purchase” or “Refinance” and the loan is to finance the initial
construction of a dwelling on the property identified in 1026.37(a)(6).
(iv) Home equity loan. If not for “Purchase”, “Refinance” or “Construction”.

As mentioned above, if it's not a purchase, refinance or construction, your only option is home equity. Makes sense, right?

Home Equity all the way in this specific scenario, as stated by Raiders2000 and Raitchjay. I know it's weird, there's no house but it is Home Equity.

The Bureau could have easily avoided having lenders scratching their heads over this by using "Other" as the purpose label for the last option.

Exactly, and that is how people should think of it. It is "everything that doesn't fit in the other 3 categories".