I've got a pair of spiffing caps for you; do for church if you like.
It was impossible for any one to deny that such a thing would be spiffing in the very highest possible degree.
"spiffing," agreed Iva, who was also inspecting the new acquisitions.
1853, of uncertain origin, probably related to spiff "well-dressed man." Spiffing "excellent" was very popular in 1870s slang. Uncertain relationship to spiff (n.) "percentage allowed by drapers to their young men when they effect sale of old fashioned or undesirable stock" (1859), or to spiflicate "confound, overcome completely," a cant word from 1749 preserved in American English slang spiflicated "drunk," first recorded 1906 in O.Henry.
Fancily and formally dressed (1877+)
[fr German spielen, ''play'']