Main Entry: un·do

Pronunciation: \ˌən-ˈdü, ˈən-\

Function: verb

Inflected Form(s): un·did \-ˈdid\; un·done \-ˈdən\; un·do·ing \-ˈdü-iŋ\

Date: before 12th century

transitive verb 1 : to open or loose by releasing a fastening
2 : to make of no effect or as if not done : make null : reverse
3 a : to ruin the worldly means, reputation, or hopes of <a politician undone by scandal> b : to disturb the composure of : upset <she's come undone> c : seduce 3intransitive verb : to come open or apart

— un·do·er \-ˈdü-ər\ noun