Deciduous means falling off at maturity or tending to fall off, and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe.
A combiner is a group of Transformers that assemble and combine their bodies into a single... A combiner is a group of Transformers that assemble and combine their bodies into a single machine, or that composite machine itself. Most combiners form a larger Super Robot with its own unique...
And that's exactly what it is: a RF Power Combiner simply combines (sum) different signals in a single output. In the above case, the signals are transmitted over port B and C go out through that output (A).