THEREIN
therein, in this, in that
(adverb) (formal) in or into that thing or place; “they can read therein what our plans are”
Source: WordNet® 3.1
Etymology
Adverb
therein (not comparable)
(pronominal) in that; in him/her/it
Anagrams
• Therien, etherin, neither, reineth
Source: Wiktionary
There*in", adv.
Definition: In that or this place, time, or thing; in that particular or
respect. Wyclif.
He pricketh through a fair forest, Therein is many a wild beast.
Chaucer.
Bring forth abundantly in the earth, and multiply therein. Gen. ix.
7.
Therein our letters do not well agree. Shak.
Source: Webster’s Unabridged Dictionary 1913 Edition