nonsynchronous

adj

1. (not-comparable)Not synchronous

   “Aldrichimica Acta Volume 30 No 4 (pdf) from Sigma-Aldrich The cyclopropanation is believed to be nonsynchronous with the alkene approaching preferentially on the side of the EWG.”

   “In a classic study imprisoned muggers were asked to rate the muggability of people by simply watching them walk down the street. The study concluded that the most attractive targets were people whose gait was perceived as "nonsynchronous".”