What's the adjective for youthful? Here's the word you're looking for.
Included below are past participle and present participle forms for the
verbs young, youthen and youthify which may be used as adjectives within certain contexts.
“Thus, in childhood's tender years, the youthful King presented the world with a model character, not only preeminent in its moral grandeur, but also without a parallel in its spiritual excellency.”
“While she appreciated her youthful looks, as she guessed women tended to do, she had come to realize that it regularly attracted the vainest of men to her side.”
“Kalaset, in a funky daylight basement with mismatched furniture, bubbles with a youthful energy and is a local favorite.”
youngsome
Seemingly young in appearance, manner, or behaviour; youthful
youngly
(archaic) Like a young person or thing; young; youthful.