Spanish words that start with j?

Java

jabonado - soaped

jabonoso - soapy

jacarandoso - blithe, merry, gay

jadeante - panting

jaldado - bright yellow

japones - Japanese

jaquecoso - tiresome, irritating

jaquelado - chequered

jarifo - showy, spruce, natty

jaro - resembling a wild boar

jaroso - full of brambles

jauto - flat, insipid, tasteless

Javan es - Javanese

jazmineo - jasminaceous

That's just the 'ja-' adjectives!