quemar
burn
crem-
related to cremation
+
-ar
verb suffix
Quemar means to burn. Think of it as crem-0 (related to cremation0) + -ar1 (verb suffix1), as burning is a key aspect of cremation.
verb
  1. burn
    To burn or set on fire
    No quemes las hojas secas en el jardín. // Don't burn the dry leaves in the garden.