Article impact refers to...
the process of judging the quality or impact of an article (or other research work) by counting the number of times other authors have cited it in their work. Article impact can be found via databases such as Scopus and Google Scholar.
People usually talk about "citation counts" as being the traditional metric used to determine article impact. On the bottom of the page, see a list of databases the library subscribes to which provide article citation counts.
Selected UND Libraries' databases with limited citation count information for articles
EBSCOhost Research Databases (e.g. Academic Search Premiere, PsycINFO, America: History and Life, CINAHL) and Scopus are now employing Plum Analytics' PlumX Metrics, which can be viewed in some databases via the Plum Print and PlumX Metrics (altmetrics) sections of an article result.
Academic Search Premiere (EBSCOhost) article-level view of PlumX Metrics: