PASTIME

n. entertainment; recreation, amusement

A hobby is a spare-time recreational pursuit.
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Noun
1. a diversion that occupies one's time and thoughts (usually pleasantly); "sailing is her favorite pastime"; "his main pastime is gambling"; "he counts reading among his interests"; "they criticized the boy for his limited pursuits"
(synonym) interest, pursuit
(hypernym) diversion, recreation
(hyponym) avocation, by-line, hobby, sideline, spare-time activity

(v. i.)
To sport; to amuse one's self.
  

(n.)
That which amuses, and serves to make time pass agreeably; sport; amusement; diversion.
  

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Riding a hobby ruins one's will.
To be excessively devoted to a pastime as to weaken the will to make progress.