misdeem v.

prefix of Germanic origin affixed to nouns and verbs and meaning "bad, wrong," from Old English mis-, from Proto-Germanic *missa- "divergent, astray" (source also of Old Frisian and Old Saxon mis-, Middle Dutch misse-, Old High German missa-, German miß-, Old Norse mis-, Gothic missa-), perhaps literally "in a changed manner," and with a root sense of "difference, change" (compare Gothic misso "mutually"), and thus possibly from PIE *mit-to-, from root *mei- (1) "to change."

Productive as word-forming element in Old English (as in mislæran "to give bad advice, teach amiss"). In 14c.-16c. in a few verbs its sense began to be felt as "unfavorably," and it came to be used as an intensive prefix with words already expressing negative feeling (as in misdoubt). Practically a separate word in Old and early Middle English (and often written as such). Old English also had an adjective (mislic "diverse, unlike, various") and an adverb (mislice "in various directions, wrongly, astray") derived from it, corresponding to German misslich (adj.). It has become confused with mis- (2).

Old English deman "to judge, decide on consideration, condemn;, think, judge, hold as an opinion," from Proto-Germanic *domjanan(source also of Old Frisian dema"to judge," Old Saxon adomian, Middle Dutch doemen, Old Norse dma, Old High German tuomen, Gothic domjan "to deem, judge"), denominative of *domaz, from PIE root *dhe- "to set, put" (compare doom). Related: Deemed; deeming. Originally "to pronounce judgment" as well as "to form an opinion." Compare Old English, Middle English deemer "a judge." The two judges of the Isle of Man were called deemsters in 17c., a title formerly common throughout England and Scotland and preserved in the surname Dempster.