young, if, perhaps, possibly, low number, immature
若 centers on the idea of something not yet fully developed: youth, immaturity, or a small number. The conditional 'if' sense extends from the idea of something still tentative or uncertain, like a young plant that could go either way.
若 originally depicted a person combing hair, suggesting compliance or softness, which led to meanings like 'young' and 'if'. The modern form combines 艹 (grass) and 右 (right), but this is a simplification; the historical connection to the original pictograph is uncertain.
Picture a young sprout 艹 just emerging, still tender and not yet fully grown. Below it, 右 (right) suggests a hand guiding it—the sprout is young and its future is still conditional, like an 'if' waiting to be decided.
For ジャク, imagine a young plant that is just a jack-in-the-box waiting to spring up: jack -> ジャク, and the young sprout is full of potential.
young; youthful
if; in case; supposing
or; otherwise
young person; youngster; young people; (the) youth
if; in case
some; few; a number of; a little (bit)
perhaps; possibly; maybe; by any chance; if I'm not mistaken
if; in case; supposing
young person
youth
wakame (species of edible brown seaweed, Undaria pinnatifida)
new leaves; young leaves; fresh verdure
perhaps; possibly; by some chance; by some possibility
young pine (tree)
young wife
to be rejuvenated; to feel young again
young greens; young herbs
men and women of all ages
rejuvenation; restoration of youth
Wakasa (former province located in the south of present-day Fukui Prefecture)