Webster Dictionary(0.00 / 0 votes)Rate this definition: 1  Fiat(noun) an authoritative command or order to do something; an effectual decree. 2  Fiat(noun) a warrant of a judge for certain processes. 3  Fiat(noun) an authority for certain proceedings given by the Lord Chancellor's signature.
HEAD LICE PRODUCTS. Our ClearLice lice treatment products will naturally get rid of lice from your head and home (clothing, bedding, furniture, carpets, and car interior) in just one day. ClearLice lice prevention products will help prevent lice from infesting your life.
Over-the-counter (OTC) medicines that are recommended for head or pubic lice include: 1  Permethrin creme rinse 1% (such as Nix), which is a common first choice for treating head lice.