Panicle:   A branched, "indeterminate" inflorescence (capitulescence in the case of asters and goldenrods), in which the capitula mature from the proximal ends to the distal ends of the branches.  ("Indeterminate" means that the length of the branches or height of the main stem can potentially become longer during the flowering period.)

Paniculiform:  Having the appearance of, but not necessarily meeting the strict definition of a panicle.  (Please also refer to the extended discussion on this subject.)

In the example below of Symphyotrichum lanceolatum, the capitulescence is said to be "paniculiform", for the capitula mature from distal end to proximal end, and the capitulescence is not strictly indeterminate.