opacar
dim
opaque
not transparent or clear
+
-ar
verb suffix
Opacar means to dim and can be understood as opaque0 + -ar1 (verb suffix1), literally meaning 'to make not transparent or clear0'.
verb
- dimTo make dull, dim, or obscure; to overshadow or eclipse.Las nubes comenzaron a opacar el sol. // The clouds began to obscure the sun.