Catenate

Catenate[{list₁,list₂,…}]

yields a single list with all elements from the list_i in order.

Catenate[{assoc₁,assoc₂,…}]

yields a list of all values in order appearing in the associations assoc_i.

Details

Catenate[{expr₁,expr₂,…}] allows the expr_i to be any mixture of lists and associations.
Any of the expr_i with head Missing are ignored.
For an association assoc, Catenate[assoc] is taken to be Catenate[Values[assoc]].

Catenate several lists:

Catenate associations:

Catenate effectively flattens the first two levels of a high-dimensional array:

Catenate strips the keys, joining all the values:

Catenate does not override the values for the same keys:

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