Rosh Hashanah

[rohsh hah-shaw-nuh, -shah-, huh-, rawsh; Ashkenazic Hebrew rohsh hah-shaw-nuh; Sephardic Hebrew rawsh hah-shah-nah] /ˈroʊʃ hɑˈʃɔ nə, -ˈʃɑ-, hə-, ˈrɔʃ; Ashkenazic Hebrew ˈroʊʃ hɑˈʃɔ nə; Sephardic Hebrew ˈrɔʃ hɑ ʃɑˈnɑ/
noun
1.
a Jewish high holy day that marks the beginning of the Jewish New Year, celebrated on the first and second days of Tishri by Orthodox and Conservative Jews and only on the first day by Reform Jews.
Also, Rosh Hashana, Rosh Hashonoh, Rosh Hashono.
Origin
1840-50; < Hebrew rōsh hashshānāh literally, beginning of the year
British Dictionary definitions for Rosh Hashanah

Rosh Hashanah

/ˈrɒʃ həˈʃɑːnə; Hebrew ˈrɔʃ haʃaˈna/
noun
1.
the festival marking the Jewish New Year, celebrated on the first and second days of Tishri, and marked by penitential prayers and by the blowing of the shofar
Word Origin
from Hebrew rōsh hasshānāh, literally: beginning of the year, from rōsh head + hash-shānāh year
Word Origin and History for Rosh Hashanah
n.

Jewish new year, 1846, from Hebrew rosh hashshanah, literally "head of the year," from rosh "head of" + hash-shanah "the year."

Rosh Hashanah in Culture
Rosh Hashanah [(rosh-huh-shah-nuh; rosh-huh-shoh-nuh)]

The festival of the New Year in Judaism, falling in September or October. Rosh Hashanah, Yom Kippur, and the eight days in between are special days of penitence.