A user of the online virtual world Second Life.

plural of second person

plural of second source

(electronics) A company that is licensed to manufacture and sell electronic components originally designed by another company (the first source).

(grammar) The form of a verb used with the pronouns thou and you (singular), or their equivalents in other languages.

(grammar) The form of a verb used with the pronouns you (plural), y'all, you guys, etc., or their equivalents in other languages.

a stream formed by the confluence of two first order streams, or of a first order stream and a second order stream

The right of an airliner of one country to land in another country for technical reasons such as refueling and maintenance.

(idiomatic) To change one's opinion, or be uneasy about a previous decision.

(cricket) The first replacement new ball in an innings; in Test cricket, usually taken after 80 overs.