C182 MISUNDERSTANDS ISP LC CLRNC AND TAXIS ONTO RWY CAUSING A HS25 ON FINAL TO GAR.

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I WAS DEP RWY 24 AT ISLIP (KISP) THIS AFTERNOON AND MISUNDERSTOOD THE CTLR'S INSTRS. THIS WAS AN INTXN TKOF; AND AN AIRLINER WAS TAXIING TO THE END OF THE RWY. I HEARD THE CTLR TELL ME TO 'HOLD SHORT ON RWY 24'; WHEN IN 20/20 HINDSIGHT HE MUST HAVE SAID 'HOLD SHORT OF RWY 24'. THE NORMAL PHRASEOLOGY IS 'POS AND HOLD' BUT I WAS SURE I HEARD THE WORD 'ON'; SO EVEN THOUGH I FELT A BIT UNCOMFORTABLE ABOUT HOLDING IN THE MIDDLE OF A RWY; INSTEAD OF ASKING FOR CLARIFICATION; I REPEATED THE INSTRUCTION WITH AN EMPHASIS ON THE WORD 'ON'; AND TAXIED INTO POS; EXPECTING A QUICK TKOF CLRNC TO FOLLOW ANOTHER PISTON ENGINED ACFT THAT HAD JUST BEEN CLRED FOR TKOF. I REMEMBER THINKING THAT IT WAS NICE THE CTLR WOULD BE CLRING ME BEFORE THE JET; SO I WOULDN'T HAVE TO A WAKE TURB DELAY; AND FIGURED THAT WAS WHY HE WANTED ME TO POS AND HOLD. WHAT I DIDN'T KNOW WAS THAT HAWKER JET WAS ON FINAL. BECAUSE I WAS ON THE RWY THE HAWKER HAD TO GAR. THE MAIN RULE I SHOULD HAVE FOLLOWED TO AVOID THIS WAS TO ASK FOR CLARIFICATION; SINCE I DID HAVE A FEELING THE INSTRUCTIONS WERE UNUSUAL; INSTEAD OF REPEATING WHAT I HEARD THE CTLR AND COUNTING ON HIM TO CORRECT ME IF THIS WAS WRONG; PARTICULARLY WITH THE RECENT EMPHASIS IN AVIATION LITERATURE ON AVOIDING RWY INCURSIONS.