Impeditive a. : Causing hindrance; impeding.

Example:
What can I do about my lack of references?

Taxonomy
imperative, imperative mood, Dictionary, Grammar, Synonyms, Definition of Imperative, adjective, Houghton Mifflin Company, Imperative Definition, word origin, Pronunciation, def, pertaining, obligation, free online English dictionary, principle, ness, The American.

Defination from the web:
Imperative - Definition of Imperative at Dictionary.com a free online dictionary with pronunciation, synonyms, and translation of Imperative. ... demands attention or action; an unavoidable obligation or requirement; necessity: It is an imperative that we help defend friendly nations. ...