爪 has two pronunciations: zhǎo (claw, talon — used in 爪子 zhǎozi) and zhuǎ (colloquial variant, also means claw). In compounds like 爪牙 (zhǎoyá, claws and teeth; henchman), use zhǎo.
usage
In everyday speech, 爪子 (zhǎozi) is more common than the bare 爪. 鸡爪 (jīzhǎo, chicken feet) is a popular Chinese snack.