Synonyms: lack, want, need

These verbs mean to be without something, especially something that is necessary or desirable. 

• Lack emphasizes the absence of something:
  ... She lacks the money to buy new shoes.
  ... The plant died because it lacked moisture. 
• Want and need stress the urgent necessity for filling a void or remedying an inadequacy:
  ... "Her pens were uniformly bad and wanted fixing" Bret Harte. 
  ... The garden needs care.

Usage Note: 

When lack is used intransitively, the present participle is generally followed by in: 

• You will not be lacking in support from me. 

Other forms of the intransitive verb are most often followed by for: 

• In the terrible, beautiful age of my prime,/I lacked for sweet linen but never for time E.B. White.
  

... The American Heritage® Dictionary of the English Language, 
http://www.thefreedictionary.com/lack