child neglect vs maltreatment

child neglect and maltreatment both are nouns.

Word	Noun	Adjective	Verb	Adverb
child neglect	Yes	No	No	No
maltreatment	Yes	No	No	No

As nouns, maltreatment is a hypernym of child neglect; that is, maltreatment is a word with a broader meaning than child neglect:

child neglect: failure of caretakers to provide adequate emotional and physical care for a child
maltreatment: cruel or inhumane treatment

Other hypernyms of child neglect include abuse, ill-treatment, ill-usage.

child neglect (noun)	maltreatment (noun)
failure of caretakers to provide adequate emotional and physical care for a child	cruel or inhumane treatment