1.
If someone drops out of college or a race, for example, they leave it without finishing what they started.
He’d dropped out of high school at the age of 16...
She dropped out after 20 kilometres with stomach trouble.
PHRASAL VERB: V P of n, V P
2.
If someone drops out, they reject the accepted ways of society and live outside the usual system.
She encourages people to keep their jobs rather than dropping out to live in a commune.
PHRASAL VERB: V P disapproval
see also drop-out