A rotating chuck (10, 100, 200) comprising: a front chuck end (12, 112, 212); and a shank-receiving bore opening out to, and extending rearwardly from, the front chuck end (12, 112, 212); the shank-receiving bore defined by a circumferentially extending bore surface (18, 218) and: having a bore axis (A B) extending through the center of the shank-receiving bore and defining forward and rearward directions; and comprising a front bore end proximate to the front chuck end (12, 112, 212) of the chuck (10, 100, 200) and a rear bore end rearward of the front bore end; the bore surface (18, 218) comprising: one or more shank abutment sub-surfaces defining a bore diameter (D B); and a groove arrangement (26, 126) recessed in the shank-receiving bore further than the one or more shank abutment sub-surfaces from the central bore axis (A B); the groove arrangement (26, 126) defining a flow path in fluid communication with the front and rear bore ends (20, 22) and comprising: an annular inlet groove at the rear bore end; one or more slanted groove portions (32, 132, 232) opening out to, and being inwardly inclined towards, the front chuck end (12, 112, 212); and one or more intermediary grooves connecting the annular inlet groove and the one or more slanted groove portions (32, 132, 232), the one or more intermediary grooves opening out only inwardly into the bore surface (18, 218) or both to the bore surface (18, 218) and an external surface of the rotating chuck (10, 100, 200); wherein the shank-receiving bore, including the groove arrangement (26, 126), is formed on a portion of the rotating chuck (10, 100, 200) having one-piece unitary construction; characterized in that the one or more intermediary grooves include one or more longitudinal groove portions (38, 238) extending parallel with the central bore axis (A B). a front chuck end (12, 112, 212); and a shank-receiving bore opening out to, and extending rearwardly from, the front chuck end (12, 112, 212); the shank-receiving bore defined by a circumferentially extending bore surface (18, 218) and: having a bore axis (A B) extending through the center of the shank-receiving bore and defining forward and rearward directions; and comprising a front bore end proximate to the front chuck end (12, 112, 212) of the chuck (10, 100, 200) and a rear bore end rearward of the front bore end; having a bore axis (A B) extending through the center of the shank-receiving bore and defining forward and rearward directions; and comprising a front bore end proximate to the front chuck end (12, 112, 212) of the chuck (10, 100, 200) and a rear bore end rearward of the front bore end; the bore surface (18, 218) comprising: one or more shank abutment sub-surfaces defining a bore diameter (D B); and a groove arrangement (26, 126) recessed in the shank-receiving bore further than the one or more shank abutment sub-surfaces from the central bore axis (A B); the groove arrangement (26, 126) defining a flow path in fluid communication with the front and rear bore ends (20, 22) and comprising: an annular inlet groove at the rear bore end; one or more slanted groove portions (32, 132, 232) opening out to, and being inwardly inclined towards, the front chuck end (12, 112, 212); and one or more intermediary grooves connecting the annular inlet groove and the one or more slanted groove portions (32, 132, 232), the one or more intermediary grooves opening out only inwardly into the bore surface (18, 218) or both to the bore surface (18, 218) and an external surface of the rotating chuck (10, 100, 200); wherein an annular inlet groove at the rear bore end; one or more slanted groove portions (32, 132, 232) opening out to, and being inwardly inclined towards, the front chuck end (12, 112, 212); and one or more intermediary grooves connecting the annular inlet groove and the one or more slanted groove portions (32, 132, 232), the one or more intermediary grooves opening out only inwardly into the bore surface (18, 218) or both to the bore surface (18, 218) and an external surface of the rotating chuck (10, 100, 200); wherein the shank-receiving bore, including the groove arrangement (26, 126), is formed on a portion of the rotating chuck (10, 100, 200) having one-piece unitary construction; characterized in that the one or more intermediary grooves include one or more longitudinal groove portions (38, 238) extending parallel with the central bore axis (A B).