1570s, "to heap or crowd together," probably from Low German hudern "to cover, to shelter" (of hens on chicks or nurses with children), from Middle Low German huden "to cover up," which is probably a frequentative form from Proto-Germanic *hud-, from PIE *keudh-, extended form of root *(s)keu- "to cover, conceal." Compare also Middle English hoderen "heap together, huddle" (c. 1300). Related: Huddled; huddling. The noun is from 1580s. U.S. football sense is from 1928.