All 5 Uses

premier
in
A Gentleman in Moscow
(Edited)

Much to the relief of the West, it seemed in the aftermath of the funeral that the man most likely to prevail was the progressive internationalist and outspoken critic of nuclear arms, Malenkov—because, like Stalin, he was appointed as both Premier of the Party and General Secretary of the Central Committee.
p. 349.9

premier = head of a government
So ten days later, Party Premier Malenkov was forced to pass his chairmanship of the Secretariat to the conservative Khrushchev, setting the stage for a duumvirate of antagonists—a delicate balance of authority between two men of contrary views and ambiguous alliances, which would keep the world guessing for a few years to come.
p. 350.1
Without a word of orchestration, the head of the table was left to Bulganin, Khrushchev, Malenkov, Mikoyan, Molotov, and Voroshilov—the six most eminent members of the Party— with the two center seats reserved for Premier Malenkov and General Secretary Khrushchev.
p. 411.5
The Count shifted his aim from the Bishop to the portrait of Stalin and shot the former Premier between the eyes.
p. 432.6 *
So, when everyone began to resume their places, Malenkov found himself stranded behind Khrushchev and Malyshev; and as the Premier of the Communist Party waited awkwardly for them to finish their conversation so that he could reclaim his seat, no one at the table even batted an eye.
p. 445.9

Definitions:

(1) (premier as in: premier architect)
the best or most important
(2) (premier as in: premier of Ontario)
title for the head of a government body in some countries
(3) (meaning too rare to warrant focus)