Encomium was certainly played by very few. That could partly be just because it's a hard word to think of, even for those who know the word. (I know the word but didn't play it. But then again, I missed a lot of words in that puzzle, like
coin and
coup and
memo.)
I found 2467 instances of
encomium and
encomiums in the News on the Web corpus. But then I realised that most of these (1722) were from Nigerian publications. It seems the Nigerians just love this word! For example, from the Nigerian daily
Blueprint on the 1st of this month:
Former President of the Senate, Senator David Mark, has showered encomium on his friend and associate, Senator Jonathan Tunde Ogbeha, who turned 74 on Wednesday (1/9/21).
Nevertheless the word is used elsewhere in the world. The
New York Post, a Murdoch tabloid not generally considered highbrow, in May this year said:
America has never been bashful about honoring those who die in its service. What is arguably the most eloquent encomium to war dead in the English language — Abraham Lincoln’s 270-word address at the Gettysburg battlefield in November 1863 — set an enduring standard.
The Wiktionary entry for the word has several usage examples, including from the writer of Westerns, Zane Grey:
"I never seen their like," was Lassiter's encomium, "an' in my day I've seen a sight of horses."
On the other hand, the OneLook dictionary site reveals that the word is listed by several sites that focus on extremely obscure words: Hutchinson's Dictionary of Difficult Words; The Phrontistery - A Dictionary of Obscure Words; Luciferous Logolepsy; and Worthless Word For The Day.
I'll have to concede that
encomium is not sufficiently common, so it will be treated as rare in future. The plural
encomia was already rare.