lock-in

(US) A sleepover party, usually held in a public place such as a church or school, in which the participants are not allowed to leave until the next morning.
(Ireland, UK) An illegal but widely-tolerated invitation-only gathering in a British pub, after the end of licensing hours, to allow regular customers the opportunity to enjoy further drinking time.
A situation in which members of an industry have agreed to adopt a certain standard and have retooled their production to meet this standard, thus making it very costly to change to a different standard.
The situation where an investor cannot trade without incurring an undesirable penalty such as taxation.