戚 is a bound form (b.f.) meaning 'relative' or 'kin', almost always appearing in the compound 亲戚 (qīnqi, 'relative'). It is not used as a standalone word in modern Chinese — you will only encounter it in fixed expressions or classical contexts. The character also appears in the idiom 休戚相关 (xiūqī xiāngguān, 'interests are closely related').