noun
lineage; family background; social standing
Refers to one's family pedigree and the social status derived from it. Often used in formal or historical contexts.
彼は門地が高い家の出身だ。
He comes from a family of high lineage.
当時は門地によって就ける職業が限られていた。
At that time, the jobs one could get were limited by one's family background.
Compound of 門 (gate, family) and 地 (land, position), suggesting the social ground or standing of a family. The exact historical derivation is uncertain, but the kanji combination conventionally represents family lineage and status.