11 across
Call
Musk
with
Washington
opening
that
ought
to
bear
fruit
(10)
Call Musk with Washington opening that ought to bear fruit (10)
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The definition is at the end of the clue.
How the clue works
The answer is built as a charade. that ought to bear fruit is the definition, and the wordplay assembles WA (the opening of Washington), then TERM (a word meaning "call"), then ELON (as in Elon Musk) to give WATERMELON.