Definitions
pleasantly (even unrealistically) optimistic
Word origin
From up- + beat.
Used in a sentence
“The notes are easy, but it's an upbeat tune and should be played fairly quickly.”
“Though he had bad news, he ended with an upbeat forecast for the future.”
“He sounded upbeat when I talked to him.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Optimistic in tone”6 letters
02“Cheerfully optimistic”6 letters
Not quite right?
"Search similar patterns."
U_____