hat·ful \ˈhatˌfu̇l\noun (pluralhatfulsalsohatsful \-tˌfu̇lz, tsˌfu̇l\) 1.: as much or as many as a hat will hold < gathered a hatful of eggs > 2.: a considerable amount or number : peck < these dives can cost you a hatful of money — T.H.Fielding > < turned down a hatful of princes — Helen B. Woodward >