Definition of Exclusively Used
The phrase in provision exempting from taxation properties exclusively used for religious worship, for schools or for purposes purely charitable, has reference to primary and inherent as over against a mere secondary and incidental use. Salvation Army v. Hoehn, Mo., 354 Mo. 107, 188 S.W.2d 826, 830.
That's the definition of Exclusively Used in Black's Law Dictionary 6th Edition. Courtesy of Cekhukum.com.