1.
Flotsam is rubbish, for example bits of wood and plastic, that is floating on the sea or has been left by the sea on the shore.
The water was full of ~ and refuse.
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2.
You can use ~ and jetsam to refer to small or unimportant items that are found together, especially ones that have no connection with each other.
...cornflake packets, bottles, and all the ~ and jetsam of the kitchen.
PHRASE