They called it a comet, 'for lack of' a better term/word. [=because they could not think of a better term/word for it]
His honesty, or 'lack thereof', is the real problem. [=the real problem is his lack of honesty]
There was 'no lack of' interest in the proposal. [=there was much interest in the proposal]
(..) are my commanding officer... Colonel Nathan R. Jessup and the Lord our God. At your request, Lieutenant Kendrick, I can have the record reflect... your lack of acknowledgement of this court as a proper authority. - Objection. Argumentative. - Sustained. Watch yourself, counselor. (..)1992 A Few Good Men