Clawson enjoyed a distinguished career as a forward with Featherstone, Bradford, Leeds, Oldham, York, Wakefield and Hull from 1962-1980 and was capped 14 times by Great Britain.
He famously fought off a severe bout of tuberculosis to enjoy a 23-year career which brought him more than 2,500 points from 640 appearances.
He won a Championship final with Leeds in 1972, when he won the Harry Sunderland Trophy as man of the match, but his finest hour came later that year when he was a member of the Great Britain team that won the Rugby League World Cup in France.
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"Our thoughts are with Terry's family at this very sad time," RFL chief executive Nigel Wood said.
"It is particularly sad and poignant that Terry's passing has come in this, a World Cup year.
"Terry will not just be remembered as a great rugby league player - he will be remembered as one of the game's great characters."
A funeral service will take place at Pontefract Crematorium next Thursday.
Leeds' players will wear black armbands in Thursday night's Super League game at Wigan as a mark of respect for both him and former general manager Joe Warham, who also passed away this week.
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