one's family and relatives; one's kith and kin
A somewhat formal or literary compound that collectively refers to one's relatives and close family members. Not an everyday conversational term; more common in written or formal contexts.
The family and relatives gathered to celebrate the New Year.
親戚 is the common word for 'relative' and is used in everyday speech. 親戚眷属 is a more formal, all-encompassing term that includes both close family and extended relatives.
眷属 alone can mean 'family' or 'dependents', but it is rarely used independently in modern Japanese. 親戚眷属 combines it with 親戚 for emphasis.
Compound of 親戚 (しんせき, 'relatives') and 眷属 (けんぞく, 'family, dependents'). The exact historical derivation is uncertain, but the combination serves to emphasize the entirety of one's familial connections.