taru-adjective, adverb taking the 'to' particle
highly acclaimed; widely praised; much talked about
A literary, somewhat archaic expression used almost exclusively in the set phrase 好評嘖々 (こうひょうさくさく), meaning 'highly praised' or 'enjoying a great reputation'. It is not used freely in modern Japanese.
See also: 好評嘖々
その新作映画は好評嘖々だ。
The new movie is highly acclaimed.
彼の小説は発売以来、好評嘖々である。
His novel has been widely praised since its release.
好評 is the common word for 'favorable reception' or 'popularity'. 嘖々 is an archaic intensifier that only appears in the fixed phrase 好評嘖々.
The exact derivation is uncertain. 嘖 is a rare kanji meaning 'to cry out' or 'to clamor', and the reduplicated form 嘖々 likely imitates the sound of many voices praising something. The word is now fossilized in the phrase 好評嘖々.