'medial ventral neurectoderm', 'lateral ventral neurectoderm' and 'intermediate ventral neurectoderm' are from FBrf0076117 (Hartenstein et al., 1994), but have no definitions.
'ventral neurectoderm medial zone', 'ventral neurectoderm lateral zone' and 'ventral neurectoderm intermediate zone' also reference FBrf0076117, so probably refer to the same thing (this paper only defines one set of medial, lateral, intermediate).
'medial ventral neurectoderm', 'lateral ventral neurectoderm' and 'intermediate ventral neurectoderm' are from FBrf0076117 (Hartenstein et al., 1994), but have no definitions. 'ventral neurectoderm medial zone', 'ventral neurectoderm lateral zone' and 'ventral neurectoderm intermediate zone' also reference FBrf0076117, so probably refer to the same thing (this paper only defines one set of medial, lateral, intermediate).