All 3 Uses of

intrusion
in
Oliver Twist

I don't want to intrude upon your secrets.'†
Chpt 5 *

intrude = unwelcome involvement or interruption

There were the faces of friends, and foes, and of many that had been almost strangers peering intrusively from the crowd; there were the faces of young and blooming girls that were now old women; there were faces that the grave had changed and closed upon, but which the mind, superior to its power, still dressed in their old freshness and beauty, calling back the lustre of the eyes, the brightness of the smile, the beaming of the soul through its mask of clay, and whispering of beauty beyond the tomb, changed but to be heightened, and taken from earth only to be set up as a light, to shed a soft and gentle glow upon the path to Heaven.†
Chpt 11

intrusively = with unwelcome involvement

As a proof of the fact, the Jew drew forth two keys from his pocket; and explained, that when he first went downstairs, he had locked them in, to prevent any intrusion on the conference.†
Chpt 26

Definitions:

(1) (intrusion)
an involvement or interruption that is unwelcome
(2) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

In geology, intrusion can reference the forcing of molten rock into fissures or between strata of an earlier rock formation.