[-ical] adj suffix [ME, fr. LL -icalis (as in clericalis clerical, radicalis radical)]: -ic "symmetrical" "geological"--sometimes differing from -ic in that adjectives formed with -ical have a wider or more transferred semantic range than corresponding adjectives in -ic
-ICAL
Meaning of -ICAL in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012