Washington, who joined Queens Park Rangers from Peterborough United in January, also hailed the impact of fellow lower-league graduates Charlie Austin of Southampton and Andre Gray, who inspired Burnley to England's top flight this year.
"Vardy is definitely an inspiration. You'd be silly to say otherwise really," Washington told British media.
"People like him, Charlie Austin, who left QPR before I arrived, Andre Gray, who's doing unbelievably at Burnley, they've opened a lot of doors for players like myself.
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"The lower leagues are being respected more now and people are starting to realise that with a bit of coaching here and there, they can mould international footballers like Vardy."
Washington was included in Northern Ireland's 23-man squad for this month's European Championship in France, where they face Poland, Ukraine and Germany in Group C.
(Reporting by Ian Rodricks in Bengaluru; Editing by John O'Brien)
