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]
(..) In graduate school, everyone thought the admissions committee made a mistake in letting them in You think I lack confidence That's not it I know I can talk well enough and I can make contact with people but I don't (..)1987 Broadcast News