Anything not readily explainable appearing to move through or be suspended in the air, primarily used to refer to objects that seem to be at least of small familiar aircraft size. Abbreviated UFO.

(astronomy) A small Solar System body (ie. asteroid, comet, or large meteoroid) whose orbit brings it into proximity with Earth's orbit.

(astronomy) a small, bright knot of nebular emission in a dark, interstellar cloud of gas and dust; thought to be mass ejected from a young star

(Internet) A cross-platform, language-independent convention for representing and interacting with objects in HTML, XHTML and XML documents.

plural of unidentified flying object

(programming) A programming paradigm that uses "objects" to design applications and computer programs.

plural of second-class object

(programming, languages) An entity of which the value can neither be passed as a parameter, nor be returned from a function, nor assigned to a variable. (Used by Raphael Finkel, the first-class object does not need to have run-time constructability according to his definition.)

(programming, languages) An entity of which the value can be passed as a parameter, but that can neither be returned from a function, nor be assigned to a variable. (Used by Raphael Finkel, the first-class object does not need to have run-time constructability according to his definition.)

(software, object-oriented programming) An adapter pattern where the adapter contains an instance of the class it wraps.