■ prefix
1》 (forming verbs and their derivatives) down; away: descend | deduct.
↘completely: denude.
2》 (added to verbs and their derivatives) denoting removal or reversal: ~ice.
3》 denoting formation from: deverbal.
Origin
from L. de 'off, from'; sense 2 via OFr. des- from L. dis- .