A score out of a hundred, invented by SEO software companies, estimating how strong a website is likely to be. Moz calls it Domain Authority, Ahrefs calls it Domain Rating.
It is useful for one thing: comparison. Knowing a competitor sits at 76 while you sit at 8 tells you the gap is years of link building, not a weekend of tweaks.
It is not a number Google uses, calculates, or has ever confirmed exists. Treating it as a target rather than a rough gauge leads to buying links to move a number that does not appear anywhere in search.
This comes up most often in Search Engine Optimisation. Getting found when someone searches for what you sell — without paying per click. Slower than ads, but it compounds and keeps working after the budget stops.
A free consult is twenty minutes and there is no pitch deck at the end of it.