Generally, definitions that start by saying that something is the name of something are weak, in part because we ordinarily define things, not their names, and in part because authors usually forget to mark the name by italicizing or quoting it. E.g.:
- Mr. Ed est equus. = OK.
- Mr. Ed est nomen equi. = OK (but usually weak).
- "Mr. Ed" est nomen equi. = OK (but usually weak).
- Mr. Ed est nomen equi. = Not OK !