Refers to a leaflet, advertisement, or supplement inserted into a newspaper or magazine, often folded. Common in publishing and direct mail contexts.
There was an insert advertisement in this morning's newspaper.
I'm in charge of designing the insert flyers.
advertising insert; inserted flyer
Standard spelling with okurigana; common in news and publishing contexts.
Irregular okurigana usage; mostly found in older or abbreviated contexts.
Variant spelling without the り okurigana; less common but still seen.
Katakana spelling used in advertising or commercial contexts.
Compound of 折り (ori, 'folding', continuative form of 折る) + 込み (komi, 'putting in', continuative form of 込む). Literally 'folding and putting in', referring to the practice of folding a sheet and inserting it into a publication.