A long-distance walk, either as a race or in aid of charity(noun)
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Use "walkathon" in a sentence
"The walkathon was the first charity project organised by Unissa's Students Representatives Council in collaborations with the Student Affairs Section."
"To raise more funds, KACA has also initiated several activities such as walkathon, open day and charity shows, he stated."
"The word 'walkathon' even has its own dictionary entry."