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“Many low‑income families are falling through the crack of the welfare system.”
They are being ignored or missed by the system.
To be unnoticed or missed, especially by a system or authority.
Students who need extra help often fall through the crack of the school’s support programs.
They are not receiving the assistance they require.
The idiom is usually used in plural form "fall through the cracks", but the singular version conveys the same idea.
Native speakers more often say "fall through the cracks"; the singular version is understandable but less common.
Do not imagine a physical crack; the phrase always refers to something being overlooked.
Originates from the literal image of something small slipping through a narrow crack and disappearing from view; first recorded in mid‑20th‑century American English.
Commonly used when discussing social policies, education, or any system where some individuals may be unintentionally excluded.