MultiTerm: TermField ReadOnly Property

Is it possible to set a field to ReadOnly?

I create a definition field, I can with a bit of trickery, set the import/export definition to ReadOnly.

So for example, if I have a TERM_UUID field, how can I make the field itself ReadOnly, so that the value cannot be changed by the end user?

I am using the SDK to view the TermFields:

               Entries oEntries = oTb.Entries;
                Entry oEntry = oEntries.Item(1);
                EntryIndexes oIndexes = oEntry.Content.EntryIndexes;
                EntryIndex oIndex = oIndexes[0];
                Console.WriteLine(oIndex.Term);
                Console.WriteLine("Number of term-level descriptive fields: " + oIndex.TermFields.Count.ToString());
                for (int i = 0; i < oIndex.TermFields.Count; i++)
                {
                    Console.WriteLine(oIndex.TermFields["i"].Name + " " + oIndex.TermFields["i"].ReadOnly);
                }

This results in:

asdasd
Number of term-level descriptive fields: 1
TERM_UUID False

But I cannot set: TermField["i"].ReadOnly = True

Logically, if the TermField has a ReadOnly property == "False", then surely one should be able to change it to "True", either programmatically or set it to "True" by default? 

Kind regards

Samuel