Dushad alone took her oath in Bhojpuri.
The lone minister from a non-Terai party was Indra Prasad Dhungel (science and technology), who is from the formerly royalist Rastriya Janashakti Party.
Nepal remains sharply divided on the language issue. On Sunday, the first vice-president of the nascent republic was suspended from his post by the Supreme Court for having taken his oath a year ago in Hindi.
Despite an order by the apex court to be sworn in again in Hindi by Sunday, Vice-President Paramananda Jha refused to do so, plunging the state into a constitutional crisis.
The ministers and MPs, however, have an edge over the vice-president. The constitution allows them to take their oath in their mother tongue.
The expansion of the cabinet by the three-month-old government, which has been severely criticised for its failure to show any improvement, comes as a bid to appease the coalition partners, especially the Hindi parties.
The Terai parties last week called a shutdown in the southern plains in support of embattled Jha and the portfolios are a means of pacifying them and ensuing that the stir is called off.