Noun
A
form
of
idealism
and
delusion
which
leads
to
extravagant
and
absurd
undertakings
or
sacrifices
in
obedience
to
a
morbidly
romantic
ideal
of
duty
or
honor
,
as
illustrated
by
the
exploits
of
Don Quixote
in
knight-errantry
.