Endeavor

15 clues
Try
Goal
Strive
Attempt
Venture
Try hard
Enterprise
Undertaking
Take pains?
Take a stab at
Concerted attempt
Determined effort
Industrious effort
Do one's darnedest
Determined undertaking
Similar answers:
Afavor
Airbender
Allende
Allinfavor
Allthoseinfavor
Allunattended
Amende
Amended
Amender
Amendes
Andindependence
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Appendectomy
Appended
Apprehender
Arendelle
Asafavor
Ascended
Ascendedsteadily