This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. Third-person singular simple present indicative form of upspring.

"Again the stallion nickered, and all that moved was a flock of wild canaries, upspringing from the flowers and shrubs of the court, rising like a green-gold spray of light flung from the sunrise."

upspringing    upsprings    upsprung   

upspringing    upsprung    upspring reel   

upstart    spring up    sprout    spring    arise