therein /ˈðɛəɹˈɪn/adverb 1phrases 1 adverb1 •in that; in that place; in him/her/it.September 1792, George Washington, letter My observation is that whenever one person is found adequate to the discharge of a duty... it is worse executed by two persons, and scarcely done at all if three or more are employed therein. Phrases with therein therein lies the rubThat is where the problem is found or located.
