IPA: /ˌʌn.dɪˈliːt/
KK: /ʌndɪˈlit/
To recover a file or record that has been deleted so that it can be used again.
I was able to undelete the important document I accidentally removed.
Past: undeleted
Past Participle: undeleted
Undelete is formed from "un-" (meaning not or opposite of) and "delete" (from Latin "delere", meaning to destroy or remove). The word "undelete" means to reverse the action of deleting, or to restore something that has been removed.
Think of 'un-' meaning not or opposite, and 'delete' meaning to remove. This helps you remember that 'undelete' means to restore something that was removed.