DROPOUT
dropout
(noun) someone who quits school before graduation
dropout
(noun) someone who withdraws from a social group or environment
Source: WordNet® 3.1
Etymology
Noun
dropout (countable and uncountable, plural dropouts)
Someone who has left an educational institution without completing the course
Someone who has opted out of conventional society.
One who suddenly leaves anything, or the act of doing so.
(cycling) The slot in the frame that accepts the axles of the wheels.
A damaged portion of a tape or disk, causing a brief omission of audio, video, or data.
Momentary loss of an electronic signal.
A technique for regularizing a neural network by discarding a random subset of its units.
Source: Wiktionary