accordion fold vs concertina fold

accordion fold and concertina fold both are nouns.

Word	Noun	Adjective	Verb	Adverb
accordion fold	Yes	No	No	No
concertina fold	Yes	No	No	No

As nouns, accordion fold and concertina fold are synonyms defined as:

accordion fold and concertina fold: a continuous parallel folding in an accordion-like fashion, that is with folds alternatively made to the front and back in zig-zag folds.

Other synonyms of accordion fold include z-fold, zig-zag fold.

accordion fold (noun)	concertina fold (noun)
a continuous parallel folding in an accordion-like fashion, that is with folds alternatively made to the front and back in zig-zag folds.	a continuous parallel folding in an accordion-like fashion, that is with folds alternatively made to the front and back in zig-zag folds.