Pastime, n.
Etymology: [Pass + time: cf. F. passetemps.]
That which amuses, and serves to make time pass agreeably; sport; amusement; diversion.
1 other Webster entry under this spelling
Pastime, v. i.
To sport; to amuse one's self. [R.]
Shades of meaning
Fernald has no entry of its own for pastime; he lists it under entertainment.
Where he writes about it:
Amusement and pastime are nearly equivalent, the latter probably the lighter word; many slight things may be pastimes which we should hardly dignify by the name of amusements. — from entertainment