frivolous

/ˈfɹɪv.əl.əs/adjective

Silly and lacking seriousness, especially at a time or in a setting that calls for it.

Example sentence

“The judge dismissed the lawsuit as frivolous.”

In law it has real teeth: a frivolous lawsuit is one with no serious legal merit, and courts can punish filing one. Its opposite is 'serious' or 'weighty'.

Related words

frostA thin layer of tiny ice crystals that forms on surfaces left out in cold air.frightA sudden, sharp burst of fear brought on by the unexpected appearance of danger, usually passing quickly.frugalCareful not to waste money or resources; spending only what is needed.friendSomeone you like, trust, and enjoy spending time with, usually a person outside your family and not a romantic partner.fruitThe part of a plant that holds the seeds, which is often sweet, colorful, and good to eat.freshmanA student of either sex in the first year of high school or university, or a new member of a legislature.