On Sunday, he took a swipe at JD(U) leader Nitish Kumar over his latest volte-face, dubbing him as a "snollygoster".

Nitish Kumar resigned as Bihar Chief Minister on Sunday, ending his 18-month alliance with Lalu Prasad Yadav's Rashtriya Janata Dal (RJD) and Congress. With the support of the BJP, he is expected to take the oath as the new Chief Minister.

Tharoor shared a social media post from 2017 when Kumar had parted ways with the grand alliance in Bihar, involving the Rashtriya Janata Dal and Congress, to rejoin the BJP despite a long-standing rivalry.

"Word of the day! Definition of *snollygoster* US dialect: a shrewd, unprincipled politician. First Known Use: 1845. Most recent use: 26/7/17," Mr Tharoor had tweeted in 2017.

Tagging that post, the former Union minister said Sunday in a post of X, "Didn't realise it would be the Word of Another Day too! #snollygoster." 

According To Merriam-Webster Dictionary:

'Snollygoster', a word for "an unprincipled but shrewd person," might derive from the word 'snallygaster', which is used to describe a mythical creature from rural Maryland that is half reptile and half bird. But 'snallygaster' appears in print after 'snollygoster'.

A favourite of political pundit Bill O'Reilly, snollygoster came into English in the 1800s to refer to a shrewd and unprincipled person, and especially an unprincipled politician.

About Nitish Kumar's Switches:

For the fourth time in the past 10 years, Bihar Chief Minister and Janata Dal-United (JD-U) President Nitish Kumar on Sunday switched his political allegiance by quitting the 'Mahagatbandhan' coalition in the state and deciding to partner with the Bharatiya Janata Party (BJP). 

Nitish on Sunday resigned as the CM of Bihar and informed Bihar Governor Rajendra Arlekar that he is walking out of the alliance with fellow INDIA bloc partners Rashtriya Janata Dal (RJD), Congress, and Left parties. 

In 2013, Nitish snapped ties with the BJP over the elevation of Narendra Modi as the prime ministerial candidate. He had been a BJP ally since 1996. Then, in 2015, he formed the Grand Alliance with RJD in Bihar.

Also Read | Nitish Kumar Walks To NDA, Again: A Look At His Many Switches 

Then, in 2017, he ditched RJD and joined hands with BJP to continue as the Chief Minister of Bihar. He contested the 2020 Bihar assembly elections with the BJP as a partner. After the JD (U)-BJP alliance won, the terms of the pre-poll pact ensured that Nitish remained as the CM of Bihar even as he was the junior partner with 45 seats and BJP was the senior partner with 78 MLAs.

Then, in 2022, he dumped BJP and resurrected the Grand Alliance and formed the government in the state with RJD, Congress, and Left parties. Now, a year and half later, the alliance has fallen apart and JD (U) under Nitish is returning to the folds of NDA again.