Sound laws · Law 32 · Consonants

Romanian T, D, S before i become ț, z, ș

T, D, S (before I, Ĕ > ie, or a yod)

Spanish

t, d, s kept

French

t, d, s kept

Italian

t, d, s kept

Portuguese

kept; t, d said [tʃ], [dʒ] before i in Brazil (dia)

Romanian

ț [ts], z, ș [ʃ]

Catalan

t, d, s kept

What happened

Before i, and before the ie that Romanian made of stressed Ĕ (see open-e), the tongue tip of t, d and s was pulled toward the palate, and Romanian turned them into new consonants: t → ț [ts], d → z (through dz), s → ș [ʃ]. That is why Romanian zice, zi, zeu begin with z where every sister has d, and șapte, șase with ș. The others kept the dentals; Brazilian Portuguese has made its own modern version, saying t and d before i as [tʃ] and [dʒ] (dia [ˈdʒiɐ], noite [ˈnojtʃi]).

Examples

Latin	Italian	Spanish	French	Portuguese	Romanian	Catalan	English relative
DĪCERE‘to say’	dire	decir	dire	dizer	zice	dir	diction
DIEM‘day’	dì	día	—	dia	zi	dia
DEUM‘god (ro zeu 'pagan god')’	dio	dios	dieu	deus	zeu	déu	deity
TERRAM‘earth (ro țară 'country')’	terra	tierra	terre	terra	țară	terra	terrain
TENĒRE‘to hold’	tenere	tener	tenir	ter	ține	tenir
SEPTEM‘seven’	sette	siete	sept	sete	șapte	set	September
SEX‘six’	sei	seis	six	seis	șase	sis	sextet
SĪC‘thus (ro și 'and')’	sì	sí	si	sim	și	sí

Decoder

Romanian z-, ț-, ș- before a vowel often match d-, t-, s- in every sister: zice → dire, decir; zi → día, dia; țară → terra; șapte → sette, siete.

Exceptions

Where an i appeared only later there is no change: DENTEM → dinte, not *zinte. The change is still alive in Romanian inflection, where a plural or second-person -i palatalizes the stem: frate → frați, cad → cazi, pas → pași. Romanian God is Dumnezeu, from DOMINE DEUS.