The word is spelled dendritic, just as you spelled it. The word means relating to or resembling a dendrite.
Dendritic
i'm not sure. I think it's a dendritic pattern
Dendritic pattern
The Amur River features dendritic drainage. This pattern of river system resembles the branching of tree roots and is common in areas with homogenous rock structures, where water flows in a branching pattern towards lower elevations.
Most Indo-Gangetic Rivers have dendritic (tree-like) drainage pattern.
I don't know about 'treillis' rivers, but the Loire river seems to me to be dendritic (in the sense of arborescent)
The dendritic pattern develops where the river channel follows the slope of the terrain. The stream with its tributaries resembles the braches of a tree , thus the name dendritic. It also flows underneath a rock that is the same hardness.
dendritic cell
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I would say Trellis because it doesn't look dendritic, but I can't be sure.
Dendritic because the rivers cross a gradual slope over one basic type of rock.
Langerhans cells