1. Being a matter of form only; lacking substance
   "a form-only requirement that is usually ignored"

See also: formal

• undead
• undecagon
• undeceive
• undeceived
• undecided
• undecipherable
• undecipherably
• undeciphered
• undeclared
• undecomposable
• undecomposed
• undecorated
• undecylenic acid
• undedicated
• undefeated
• undefendable
• undefended
• undeferential
• undefiled
• undefinable
• undefined
• undelete
• undelineated
• undemanding
• undemocratic