Longman Dictionary of Contemporary English
child benefit
noun
EXAMPLES FROM CORPUS
▪ Against this he would gain an extra £4.60 a week in increased child benefit from Labour.
▪ Are changes such as means-testing child benefit and state pensions simply unthinkable?
▪ As a first step pensions and child benefit were to be raised and long-term supplementary benefit extended to the long-term unemployed.
▪ If so, we should be told how they will meet their spending commitments on child benefit and pensions.
▪ The former refers to payments such as pensions, supplementary benefit, family income supplement, child benefit, and so on.
▪ Those without work have the value of their child benefit subtracted from their total welfare payments.
▪ With child benefit included their income has been increased from £124.20 to £148.62 a week.
Wiktionary
child benefit
n. (context UK English) A regular government payment made to parents or guardians for each child up to a certain age
Wikipedia
Child benefit
Child benefit (children's allowance) is a social security payment which is distributed to the parents or guardians of children, teenagers and in some cases, young adults.