Abstract: A machining tool holder includes: a sleeve defining a central channel and a lubricant channel and formed with annular inner grooves and fastener holes, the lubricant channel having a truncated spherical end region; fasteners extending through the fastener holes; first O-rings retained in the annular inner grooves; a truncated spherical nozzle mounted rotatably in the truncated spherical end region; and an abutting mechanism having an abutting shaft and an second O-ring. The abutting shaft extends into the central channel and defines a retaining groove. The second O-ring is retained in the retaining groove and extends outwardly of the retaining groove beyond an end face of the abutting shaft.