noun
family crest register
A book or album containing a collection of family crests (家紋), used for reference or record-keeping.
古い紋帳を開いて、先祖の家紋を調べた。
I opened an old family crest register and looked up my ancestors' family crest.
Compound of 紋 (mon, 'crest') and 帳 (chō, 'register, book').