to put someone's or something's name on an official list:
on a list[intransitive and transitive]PGC
The tanker is registered in Rotterdam.
How many students have registered for English classes?
You must bring your insurance card with you when you register with a dentist or doctor.
register a birth/death/marriage
The baby's birth was registered this morning.
be registered (as) unemployed/disabled etc British English (=be on an official list of a particular group)
to officially state your opinion about something so that everyone knows what you think or feel:
state your opinion[transitive] formal
The delegation registered a formal protest with US embassy officials Wednesday.
if something registers, or if you register it, you realize or notice it, and then remember it:
realize[intransitive usually in negatives, transitive]
She had told me her name before, but I guess it didn't register.
I'd been standing there for several minutes before he registered my presence.
if an instrument registers an amount or if something registers on it, the instrument shows that amount:
measurement[intransitive and transitive]TM
The thermometer registered 98.6°.
The earthquake registered 7.2 on the Richter scale.
to show or express a feeling:
show a feeling[transitive] formal
Her face registered shock and anger.
mail[transitive] British EnglishTCM
to send a package, letter etc by registered post:
Did you register the parcel?