pentaquark

pen·ta·quark

Today it means: Any of a class of subatomic particles (previously hypothetical, since detected, subject to confirmation) consisting of a group of five quarks (compared to three quarks in normal baryons and two in mesons), or more specifically four quarks and one antiquark (symbol Θ). Full definition →

English quark ← Ancient Greek πεντᾰ- (pentă-) ← Proto-Hellenic *pénkʷe