Link profile
The aggregate characteristics of all links pointing to a site: source diversity, anchor text distribution, follow ratio, topical relevance…
LinksLink growth rate
Link velocity
The rate at which a site or page acquires new backlinks over time; abrupt, unexplained spikes are a common signature of manipulation.
In full
There is no published velocity threshold, and genuine viral coverage produces enormous natural spikes, so velocity alone proves nothing. Its diagnostic value lies in context: a sudden burst of links with identical anchors from unrelated low-quality domains reads very differently from a burst of press coverage after a launch. Tracking velocity is mostly useful for spotting third-party activity you did not commission.
Example
A newly launched brand acquires 200 referring domains in three days from a national news story — high velocity, entirely natural.
Related terms
Link spam
Google's spam policy category covering links intended to manipulate rankings: buying or selling links, excessive exchanges, automated link…
Digital PR
Earning editorial coverage and links from media outlets through newsworthy assets — original data, expert commentary, campaigns — rather…
Negative SEO
Attempts to damage a competitor's rankings, typically by pointing spam links at their site, scraping their content, or fabricating removal…
Referring domains
The number of unique domains linking to a site or page, generally a more meaningful measure of link popularity than raw backlink count.