A pentaquark is a human-made subatomic particle, consisting of four quarks and one antiquark bound together; they are not known to occur naturally, or exist outside of experiments specifically carried out to create them. Wikipedia

Exotic baryon consisting of five quarks Wikidata

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). Wiktionary

Subatomic particle consisting of five quarks. Wiktionary (translation)