forming words, with the meanings:
to do the opposite of (a specified action)
disestablish
disappear
to deprive of or, remove (something specified) from
disarm
dismember
to exclude or expel from
disbar
opposite or absence of
disarray
disbelief
not
disagreeable
dishonest
completely
disannul
disgruntled
= dys-
disfunction
[Middle English dis-, des- via Old French des-, dis- from Latin dis-, literally ‘apart’; (sense 5) by folk etymology]