Accordance is agreement with a rule. In accordance with the regulations, in accordance with his wishes, act in accordance.
It appears almost only in the phrase in accordance with, which is official language for according to or as required by. Plain writing usually prefers under the rules, but the phrase is fixed in contracts and statutes.
1nounaccordanceAgreement with a rule.
“The money was shared out in accordance with her grandmother's wishes.”
accordance is an agreement.
Old French acordance comes from acorder, from Latin ad cor, to the heart — to bring into agreement.
* compliance First attested around 1300.
Etymology from Wiktionary, CC BY-SA