Yes, this David Meister dress (left) is very colorful, but I think the pattern is fun and youthful, yet not overdone -- and not too floral. And the simple sheath design of the dress, the high neck, and its knee-length make the pattern fine for work, although perhaps not for a really important meeting. Obviously, I would tone down the bright pattern by pairing the dress with a black or tan or other neutral-colored cardigan.
I found the dress via Nordstrom's current sale on dresses: up to 40% off. This dress is made from cotton and spandex. Originally $330, it is 40% off at $198. Find it here.
Browsing through the sale, there are a few other work-appropriate vegan dresses of interest: Burberry's stretch trench dress in taupe (made from cotton and elastane; more appropriate for business casuals days; originally $595, on sale for $395; here); Jones New York Collection's sheath dress in white (made from polyester, viscose, and elastane; originally $159, on sale for $106; here); Calvin Klein's cargo shirtdress in black and khaki, which I have blogged about before (made from polyester and spandex; originally $118, on sale for $70; here; and Maggie London's ruche matted jersey dress in the black and off-white print pictured right (made from polyester and spandex; originally $128, on sale for $64; here).