intruder
UK[ɪnˈtruːdə]US[ɪnˈtruːdər]
n
a person who enters a place or situation without permission or welcome.
n
an aircraft or vehicle that has entered an area without authorization.
Morpheme Breakdown
in
trud
er
in
in, into, on, against
trud
to thrust, push, shove
er
a person or thing that does something
Etymology
the word intruder is built upon the latin verb intrudere, which itself is a compound of the prefix in- ("into") and the verb trudere ("to thrust"). the literal sense of thrusting or pushing one's way into a space evolved into the broader concept of entering forcibly or without right. entering english via old french in the late 15th century, the agent suffix -er was added, solidifying its meaning as "one who forces their way in." thus, the modern abstract meaning of an unwelcome or unauthorized entrant logically extends from this ancient image of physical pushing.
Analysis
Structure: in + trud + er
in: a latin prefix meaning "in, into, on, against".
trud: from latin trudere, meaning "to thrust, push, shove".
er: an english agent noun suffix meaning "a person or thing that does something".
Examples
the security alarm was triggered by an intruder.
she felt like an intruder at the private family gathering.
military radar detected an unidentified aerial intruder.