Formalin.
An evening gown.
An event with a formal dress code.
A formal parameter.
Being in accord with established forms.
Official.
Relating to the form or structure of something.
Relating to formation.
Ceremonial or traditional.
Proper, according to strict etiquette; not casual.
Organized; well-structured and planned.
Relating to mere manipulation and construction of strings of symbols, without regard to their meaning.