Dharma as a citadel against the false; the secure nirvāṇa abode; the sūtras as the guardians of truth.

A Dictionary of Chinese Buddhist Terms, William Edward Soothill and Lewis Hodous

正法可杜防非法，猶如城池之防患外敵，故稱法城。準此，一切經法亦稱法城，此乃因經法可守護正法之故。又涅槃妙果乃安身之處，故亦稱法城。無量壽經卷上（大一二‧二六六上）：「嚴護法城，開闡法門；洗濯垢污，顯明清白；光融佛法，宣流正化。」〔維摩經佛國品、無量壽經義疏（慧遠）〕

佛光電子大辭典

p3377

dharma-nagara

佛教漢梵大辭典

P1966

法城 (fǎ chéng) 　( “the Dharma-city (the Dharma, which is to be protected from harm, is here compared to a city)” )

{《漢語大詞典》5.1040a(正法華經)} ; {《大漢和辞典》6.1049b(佛典)} ;

Dharmarakṣa: {99c24} 時佛知心，然其末世當護法城(p)

{K.224.1-}

Kumārajīva: {not found at L.30b29}

Dharmarakṣa: {100b7} 於是善蓋 得柔順忍 佛滅度後 守護法城 精進不懈 得五神通 總持、辯才 開化一切(v)

{K.224.1-}

Kumārajīva: {not found at L.30b29} 

A Digital Edition of A Glossary of Dharmarakṣa translation of the Lotus Sutra by Seishi Karashima, 1998