A lot of people seem to think that "ethics" and "morals" mean something different–but those people who think this rarely seem to agree on what exactly the supposed difference is, nor have I ever seen anyone who thought this able to cite an authoritative source for their proposed distinction. The difference between "ethics" and "morals" is etymological – the first word comes from Greek, the second word comes from Latin. The traditional and historically well-established usage is that they are synonyms–most dictionaries and thesauruses treat them as such.
Part of the issue, I think, is the term "moral" often has religious/traditional/conservative connotations, whereas the word "ethical" often has more secular/progressive connotations. But, a difference in connotation does not require a difference in denotation. And many of the proposals to define these words differently rely on secularist assumptions, about a distinction between a "personal" or "private" and "public" sphere, which is a distinction which appeals to secular progressives but which many religious conservatives will question.
Part of the issue, I think, is the term "moral" often has religious/traditional/conservative connotations, whereas the word "ethical" often has more secular/progressive connotations. But, a difference in connotation does not require a difference in denotation. And many of the proposals to define these words differently rely on secularist assumptions, about a distinction between a "personal" or "private" and "public" sphere, which is a distinction which appeals to secular progressives but which many religious conservatives will question.