appropriate to one's station; within one's means; fitting one's social position
Describes behavior, lifestyle, or spending that matches one's social status or financial situation. Often used in the set phrase 身分相応に暮らす (live within one's means).
I try to live within my means.
He drives a car that suits his social standing.
分相応 is a more common synonym with the same meaning, but 身分相応 explicitly includes the nuance of social status (身分).
Compound of 身分 (social status) and 相応 (suitable, appropriate).