diligent
(adj) constant in effort to accomplish something, attentive and persistent
disband
(v) to break and dissolve
discourage
(v) to deprive of courage, to hinder by disfavor
disparage
(v) to degrade, belittle, debase, to lower in rank
dissension
(n) strong disagreement, contention
dissuade
(v) to convince not to try or do
dolt
(n) a stupid person
dubious
(adj) doubtful; questionable
edify
(v) to build, establish, to instruct on how to improve
eccentric
(adj) odd, peculiar, erratic, deviating from the norm