Index naming restrictions

Is there a way to restrict the use of certain words or patterns for an index name?

foo* = good
bar* = bad

Yes - https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-index_.html#index-creation

That only applies to auto-created indexes as far as I understand. I need a forced index name restriction. I need the restriction applied to both manually and auto created indices.

Then no.