As nouns the difference between codicil and appendage
is that codicil is (legal) an addition or supplement that explains, modifies, or revokes a will or part of one while appendage is an external body part that projects from the body.
codicil
English
Noun
(
en noun)
(legal) An addition or supplement that explains, modifies, or revokes a will or part of one.
* 2005 , , (Bloomsbury Publishing, paperback edition, p. 378)
- If Nick answered a question Wani listened to him and then gave a flat little codicil or correction.
appendage
English
Noun
(
en noun)
an external body part that projects from the body
a natural prolongation or projection from a part of any organism
a part that is joined to something larger
Synonyms
* extremity, member
* outgrowth, process