ˈrædɪkəl adj. & n. --adj. 1 of
the root or roots;
fundamental (a radical error). 2 far-reaching;
thorough;
going to the root (radical change). 3 a advocating thorough
reform;
holding extreme political views;
revolutionary. b (of a
measure etc.) advanced by or
according to principles of
this kind. 4 forming the
basis;
primary (the radical idea). 5
Math. of the root of a
number or
quantity. 6 (of
surgery etc.) seeking to
ensure the
removal of
all diseased tissue. 7 of the roots of words. 8 Mus. belonging to the root of a chord. 9
Bot.
of, or springing
direct from, the root. 10
hist. belonging to an extreme
section of the
Liberal party. 11 US hist. seeking extreme anti-South
action at the
time of the
Civil War. --n. 1 a
person holding radical views or belonging to a radical party. 2 Chem. a a
free radical. b an
element or
atom or a
group of
these normally forming
part of a compound
and remaining
unaltered during the compound's
ordinary chemical changes. 3 the root of a
word. 4 a fundamental
principle; a basis. 5 Math. a a quantity forming or expressed as the root of
another. b a radical
sign. øradical sign indicating the
square,
cube,
etc., root of the number
following. øøradicalism n. radicalize v.tr. & intr. (also -ise). radicalization n. radically adv. radicalness n. [ME f. LL radicalis f. L
radix radicis root]
