val/vail

be strong; be worth

Spelled val, vail · valere 'be strong, be well, be worth'

Latin valere means being strong: the valiant show courage, the valid hold firm, and people convalesce as strength returns.

Words built from it

valid — Sound, well-founded, or officially acceptable.
val (be strong) + -id (having the quality of)
valor — Great courage in danger.
val (be strong) + -or (state or quality)
value — The worth or importance of something.
val (be worth)
valiant — Brave and determined.
vail (be strong) + -ant (being)
prevail — Win out or prove stronger.
pre- (before) + vail (be strong)
convalesce — Recover strength after illness.
con- (thoroughly) + val (be strong) + -esce (become)
equivalent — Equal in value, meaning, or effect.
equi- (equally) + val (be worth) + -ent (being)

valley — From Latin vallis, meaning a valley, rather than valere, meaning to be strong or worth.