Oblivious means completely unaware of what is happening around you. Oblivious to the noise, blissfully oblivious, walk on oblivious.
It takes to or of, with to now much the commoner. It usually carries a note of amusement or reproach: somebody oblivious is missing what everybody else can see. Blissfully oblivious is the fixed phrase. Note that the older sense was forgetful rather than unaware — the Latin is about forgetting, and oblivion is where forgotten things go.
1adjectiveobliviousCompletely unaware of what is happening around you.
“Lost in his music, he was oblivious to the fire alarm ringing.”
oblivious is a state of unawareness.
Latin obliviosus comes from oblivisci, to forget. Oblivion is the same forgetting, and the shift from forgetful to unaware happened in English.
Latin
oblīviōsus — forgetful, oblivious
Middle English
oblivious
English, today
oblivious
Built from
From Middle English oblivious, from Latin oblīviōsus (“forgetful, oblivious”), formed from oblīvium (“forgetfulness, oblivion”) + -ōsus (“full of, overly, prone to”), from oblīvīscor (“to forget”).
Etymology from Wiktionary, CC BY-SA