sweeten

/ˈswitən/
verb
  1. To make something taste sweeter by adding sugar or another sweet substance.
    • She sweetened the lemonade with sugar until it was just right.
    • The baker sweetened the cake batter with vanilla and brown sugar.
    • I always sweeten my coffee with a little honey.
  2. To make a situation, offer, or relationship more pleasant or attractive.
    • The company sweetened the job offer with a signing bonus.
    • A sincere apology can sweeten even the most difficult conversation.
    • He tried to sweeten the deal by offering free delivery.
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