RADICAL a. 13 definitions
Hence: Of or pertaining to the root or origin; reaching to the center, to the foundation to the ultimate sources to the principles, or the like: original; fundamental; thorough-going; unsparing; extreme; as, radical evils; radical reform; a radical party. The most determined exertions of that authority, against them, o…
REACTION n. 5 definitions
water wheel driven by the reaction of water, usually one in which the water, entering it centrally, escapes at its periphery in a direction opposed to that of its motion by orifices at right angles, or inclined, to its radii.