What is commonly called an absent man is commonly either a very weak or a very affected man.
Chesterfield.

Syn. -- Absent, Abstracted. These words both imply a want of attention to surrounding objects. We speak of a man as absent when his thoughts wander unconsciously from present scenes or topics of discourse; we speak of him as abstracted when his mind (usually for a brief period) is drawn off from present things by some weighty matter for reflection. Absence of mind is usually the result of loose habits of thought; abstraction commonly arises either from engrossing interests and cares, or from unfortunate habits of association.

If after due summons any member absents himself, he is to be fined.
Addison.