隠し引き出し【かくしひきだし】
secret drawer, hidden drawer
隠す【かくす】
to hide, to conceal
隠居【いんきょ】
retirement (from work), leading a quiet life (after retirement), retired person, retiree, surrendering headship of the family (pre-WWII)
隠匿【いんとく】
concealment (esp. of wrongdoings or criminals), sheltering, harboring
隠語【いんご】
secret language, jargon, cant, argot, slang