[4][5] One definition proffered by Congolese linguist Salikoko Mufwene is "languages spoken as vernaculars or as lingua francas outside their homelands and by populations other than those ethnically or nationally associated with them".
Another indicator is the number of native speakers, which although it is not in itself a criterion for globality, empirically correlates positively with it and may influence it indirectly by making the language more attractive.
[9] Arabic has been described by Salikoko Mufwene as a world language—albeit a second-tier one after English and French due to limited use as a lingua franca—on the grounds that is a liturgical language amongst Muslim communities worldwide.
[1]: 116–117 Ammon and Mufwene both posit that what sets English apart as the foremost world language is its use as a lingua franca,[6]: 43 [1]: 103 whereas Crystal focuses on its geographical distribution.
[1]: 102 Salikoko Mufwene also considers it a world language—albeit a second-tier one after English and French due to limited use as a lingua franca—on the grounds that it is used as a vernacular by people neither ethnically nor nationally associated with it outside of Spain.