treebank /ˈtɹiː.bæŋk/noun 1verb 1forms 3 noun1 •A database (corpus) of sentences which are annotated with syntactic information, often in the form of a tree.If one wants to use a treebank for linguistic investigation, […]. — 2003 verb1 •To parse and annotate sentences according to a treebank. formstreebanked · treebanking · treebanks