The word covers two kernels: almonds, which mainland packs must label 扁桃仁 or 巴旦木, and apricot kernels, which flavor desserts such as 杏仁豆腐 and the drink 杏仁露.
In Chinese, 杏仁 originally refers to apricot kernels (used in traditional medicine and cooking). The word is now also used for almonds, though technically almonds are 扁桃仁.