Bhagavad Gita: Chapter 17/Verse 23

ॐतत्सदिति निर्देशो ब्रह्मणस्त्रिविधः स्मृतः ।


ब्राह्मणास्तेन वेदाश्च यज्ञाश्च विहिताः पुरा ॥१७- २३॥

oṃtatsaditi nirdeśo brahmaṇastrividhaḥ smṛtaḥ ।

brāhmaṇāstena vedāśca yajñāśca vihitāḥ purā ॥17- 23॥

"Om Tat Sat," is the known three-fold designation of Brahman. By this are Brahmans, the Vedas, and  sacrifices are anciently ordained. 


oṃ = the sacred syllable 

tat (neuter, nominative, singular) = that

sat (neuter, nominative, singular) = true

iti (punctuation) (indeclinable) = (close quotes)

nirdeśas (masculine, nominative, singular) = designation

brahmaṇas (neuter, genitive, singular) = of Brahman 

trividhas (masculine, nominative, singular) = of three kinds 

smṛtas (past passive participle, masculine, nominative, singular) = known 


brāhmaṇās (masculine, nominative, plural) = the Brahmans 

tena (masculine, instrumental, singular) = by this

vedās (masculine, nominative, plural) = the Vedas

ca (conjunction) (indeclinable) = and 

yajñās (masculine, nominative, plural) = sacrifices 

ca (conjunction) (indeclinable) = and 

vihitās (past passive participle, masculine, nominative, plural) = ordained 

purā (adverb) (indeclinable) = ancient