Definition of "unnoticed"

In the midst of a world war many centenaries pass unnoticed, but one which fell on August 2, namely, the opening of Fenchurch Street station, is deserving of record.

1941 September, “Notes and News: The London & Blackwall Cable Railway”, in Railway Magazine, pages 424–425

The announcement was slipped out almost unnoticed on the last day before Parliament was dissolved to prepare for a General Election.

2019 November 20, “Government delays Heathrow rail to consider other modes”, in Rail, page 25

The change of blue of the flags adorning the Elysée Palace was first made a year ago but went largely unnoticed.

2021 November 11, “Macron reverts French flag to navy blue from lighter EU shade”, in euronews