'Solemn' in the Bible

The ways of Zion do mourn, because none come to the solemn feasts: all her gates are desolate: her priests sigh, her virgins are afflicted, and she is in bitterness.

The Lord hath set at nought all my mighty men in the midst of me; He hath called a solemn assembly against me to crush my young men: The Lord hath trodden as in a winepress the virgin daughter of Judah.

And he hath violently taken away his tabernacle, as if it were of a garden: he hath destroyed his places of the assembly: the LORD hath caused the solemn feasts and sabbaths to be forgotten in Zion, and hath despised in the indignation of his anger the king and the priest.

The Lord hath cast off his altar, he hath abhorred his sanctuary, he hath given up into the hand of the enemy the walls of her palaces; they have made a noise in the house of the LORD, as in the day of a solemn feast.

Thou hast called as in a solemn day my terrors round about, so that in the day of the LORD'S anger none escaped nor remained: those that I have swaddled and brought up hath mine enemy consumed.