Documentation for infix (>=), infix ⊇ assembled from the following pages:

Language documentation: Operators §

From Operators

(Operators) infix (>=), infix ⊇ §

multi sub infix:«(>=)»($a,$b --> Bool:D)

Superset of or equal to operator.

Returns True if $a is a superset of $b, i.e., that all the elements of $b are elements of $a but $a is a larger or equal sized set than $b.

say (1,2,3) (>=) (2,3,1); # OUTPUT: «True␤» 
say (1,2,3) (>=) (2,3);   # OUTPUT: «True␤» 
say 4 ⊇ (1,2,3);          # OUTPUT: «False␤» 

Language documentation: Sets, bags, and mixes §

From Sets, bags, and mixes

(Sets, bags, and mixes) infix (>=), infix ⊇ §

Returns True if $a is a superset of or equal to $b, else False. More information, Wikipedia definition.