(ice hockey) An empty-net goal.

(idiomatic) To be losing enthusiasm or willingness; to lack motivation.

plural of empty space

(graph theory) A graph with vertices but no edges.

(psychotherapy) A chair which is used to personify the client's object of conflict / A podium or chair left empty to highlight the absence of someone from a debate.

(transitive, debating) To draw attention to (a person who is absent from a debate) by providing an empty podium or chair which they would have occupied.

(transitive) To completely empty.

plural of empty sum

(linguistic morphology) A purely formal morpheme with no semantic content.

(idiomatic) To make the utmost effort; to contribute to the absolute limit of one's energy and abilities.