noun, noun which may take the genitive case particle 'no'
hard type; hardball; hard (tennis)
Used in sports contexts to distinguish a regulation hard ball or formal style from a softer or simplified version (軟式). Common in compounds like 硬式野球 (hardball baseball) and 硬式テニス (regular tennis).
See also: 軟式
I started playing hardball baseball in high school.
A regular tennis ball is heavier than a soft tennis ball.
When I entered high school, I switched from softball to hardball.
He has been playing hardball since junior high.