(verb)
to spend or take a long time doing something, for example to delay taking a course of action (i.e. to procrastinate) or to be slow in moving to some place (i.e. to be leisurely, to saunter);
e.g. I advise you not to linger on sending in your application.
(verb)
to be slow in dying or disappearing, for example to remain alive for an extended period of time while being gradually depleted of life, or to remain present in some context while losing importance, influence, or strength;
e.g. The smells of the feast linger in the rest of the house for a few days.