bittersweet
noun
bit·​ter·​sweet
| \ ˈbi-tər-ˌswēt
\
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Definition of bittersweet
(Entry 1 of 2)
1
: something that is bittersweet
especially
: pleasure accompanied by suffering or regret
… the bittersweet of their long separation … — Christopher Morley
2 botany
a
: a poisonous Eurasian woody vine (Solanum dulcamara) of the nightshade family that has purple flowers and oval reddish berries and is naturalized (see naturalize sense 4) in North America
b
: a North American poisonous woody vine (Celastrus scandens) of the staff-tree family having clusters of small greenish flowers succeeded by yellow capsules (see capsule entry 1 sense 2a) that open when ripe and disclose the scarlet aril