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WordNet
superior thalamostriate vein

n. a long vein that helps to form the internal cerebral vein

Wikipedia
Superior thalamostriate vein

The superior thalamostriate vein or terminal vein commences in the groove between the corpus striatum and thalamus, receives numerous veins from both of these parts, and unites behind the crus of the fornix with the choroid vein to form one of the internal cerebral veins.