ATCT LCL CTLR AT VABB MAY HAVE USED CONFUSING PHRASEOLOGY WHEN HE WANTED AN MD11 FLT TO HOLD SHORT OF THE RWY FOR LNDG TFC.

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EVENT OCCURRED WHILE HOLDING SHORT OF RWY 27 AT MUMBAI; INDIA'S CHHATRAPAH SHIVAJI INTL ARPT. WE HAD ALREADY RECEIVED OUR ATC DEP CLRNC DURING THE TAXI OUT. WE WERE HOLDING SHORT OF RWY 27 AT THE HOLD SHORT LINE FOR APPROX 3 MINS WHEN THE TWR CTLR CALLED US AND SAID 'ACFT X CLRED FOR TKOF RWY 27; BIMOT 1A; CLB TO FL280 BY BIMOT.' THE FO REPEATED 'ACFT X CLRED FOR TKOF' AND REPEATED THE REST OF THE CLRNC. TWR CTLR REPEATED THE CLRNC BACK; AND THE FO REPEATED ONCE AGAIN 'ACFT X CLRED FOR TKOF;' AND REPEATED THE REST OF THE CLRNC AGAIN. AFTER THAT; THE TWR CTLR DID NOT RESPOND. WE THEN VISUALLY CLRED THE APCH AND DEP CORRIDOR FOR LNDG TFC; AND ALSO NOTED AN ACFT ON TCASII; WHICH WAS ON ABOUT AN 8 MI FINAL. CAPT STARTED TO TAXI TOWARD THE RWY WHEN A SECOND CTLR CAME ON THE RADIO AND SAID 'ACFT X; CONFIRM CLR OF RWY.' THE CAPT IMMEDIATELY STOPPED THE ACFT; AND THE NOSE STOPPED ABOUT HALFWAY BTWN THE HOLD SHORT LINE; AND THE EDGE OF THE RWY; AND THE FO REPLIED 'NEGATIVE; ACFT X IS NOT CLR OF THE RWY.' AT THIS POINT; TWR DIRECTED AN ACFT Y ON APPROX A 4 MI FINAL TO EXECUTE A GAR. (THE SECOND CTLR THAT TOLD US TO CONFIRM CLR OF THE RWY MAY HAVE BEEN A SUPVR.) IN SUMMARY: THE SAME ATC DEP CLRNC WAS GIVEN TO US WHILE TAXIING OUT; AND WHILE HOLDING SHORT OF RWY 27. ALSO; WHILE HOLDING SHORT OF RWY 27; THE TWR CALLED AND TOLD US WHAT ALL 3 CREW MEMBERS HEARD AS 'CLRED FOR TKOF.' THE FO REPEATED 'CLRED FOR TKOF' BOTH TIMES TO THE TWR CTLR; BUT WAS NEVER CORRECTED. A POSSIBLE CONTRIBUTING FACTOR WAS THE ATC PHRASEOLOGY USING THE WORD 'TKOF' WHEN ISSUING DEP INSTRUCTIONS WHILE HOLDING SHORT.