A rotary cutting tool, having a tool longitudinal axis, defining a forward to rearward direction (D F, D R) and about which the rotary cutting tool is rotatable in a rotational direction, the rotary cutting tool comprising a tool holder and a tool body releasably attached to the tool holder at the holder forward end thereof, wherein: the tool holder comprises: a holder peripheral surface extending circumferentially along the tool longitudinal axis and forming a boundary of a holder front surface at the holder forward end; and an adjustment arrangement comprising a biasing member which is movably attached to the tool holder and comprises a biasing portion; and the tool body comprises: opposing body forward and rearward surfaces (26, 28) and a body peripheral surface extending therebetween; and a plurality of angularly spaced apart cutting portions, each comprising an insert pocket disposed at the body peripheral surface and configured to retain a cutting insert, the plurality of cutting portions comprising an adjustable cutting portion, wherein the adjustable cutting portion is adjustable between a non-flexed position and a flexed position; and wherein in the flexed position, the adjustable cutting portion is elastically deformed in the forward direction (D F) due to the biasing portion pushing against the body rearward surface of the tool body. the tool holder comprises: a holder peripheral surface extending circumferentially along the tool longitudinal axis and forming a boundary of a holder front surface at the holder forward end; and an adjustment arrangement comprising a biasing member which is movably attached to the tool holder and comprises a biasing portion; and a holder peripheral surface extending circumferentially along the tool longitudinal axis and forming a boundary of a holder front surface at the holder forward end; and an adjustment arrangement comprising a biasing member which is movably attached to the tool holder and comprises a biasing portion; and the tool body comprises: opposing body forward and rearward surfaces (26, 28) and a body peripheral surface extending therebetween; and a plurality of angularly spaced apart cutting portions, each comprising an insert pocket disposed at the body peripheral surface and configured to retain a cutting insert, the plurality of cutting portions comprising an adjustable cutting portion, wherein the adjustable cutting portion is adjustable between a non-flexed position and a flexed position; and wherein in the flexed position, the adjustable cutting portion is elastically deformed in the forward direction (D F) due to the biasing portion pushing against the body rearward surface of the tool body. opposing body forward and rearward surfaces (26, 28) and a body peripheral surface extending therebetween; and a plurality of angularly spaced apart cutting portions, each comprising an insert pocket disposed at the body peripheral surface and configured to retain a cutting insert, the plurality of cutting portions comprising an adjustable cutting portion, wherein the adjustable cutting portion is adjustable between a non-flexed position and a flexed position; and wherein in the flexed position, the adjustable cutting portion is elastically deformed in the forward direction (D F) due to the biasing portion pushing against the body rearward surface of the tool body.