Not To Be Confused With
Dogma is the highest grade of teaching — formally defined and binding. A “doctrine” is any teaching; not every doctrine has been raised to the level of dogma.
From Greek dogma, “that which seems good, a decree.” In theology a dogma is a truth the Church has formally defined as divinely revealed and binding — the Trinity, the two natures of Christ, the bodily resurrection. To deny a dogma is heresy by definition.
Traditions differ on what counts as dogma and who can define it, but all distinguish the irreformable core from secondary opinions.