Solution

VOLUNTARILY

2 clues

By choice

Word class: Adverb
Nature of clue: Synonym
Difficulty: Easy
Sources: Boatload Puzzles

Willingly

Word class: Adverb
Nature of clue: Synonym
Difficulty: Very easy
Sources: Boatload Puzzles

Other solutions to Willingly

Words are categorized by artificial intelligence: there can be mistakes.