Meaning of -ER in English

-ER

~ 1

■ suffix

1》 denoting a person or thing that performs a specified action or activity: farmer.

2》 denoting a person or thing that has a specified attribute or form: two-wheeler.

3》 denoting a person concerned with a specified thing: milliner.

4》 denoting a person belonging to a specified place or group: city-dweller.

Origin

OE ~e , of Gmc origin.

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~ 2

■ suffix forming the comparative of adjectives (as in bigger ) and adverbs (as in faster ).

Origin

OE suffix -ra (adjectival), -or (adverbial), of Gmc origin.

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~ 3

■ suffix forming nouns used informally, usually by distortion of the root word: footer.

Origin

prob. an extended use of ~ 1 ; orig. Rugby School sl., later adopted at Oxford University.

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~ 4

■ suffix forming frequentative verbs such as patter .

Origin

OE ~ian , -rian , of Gmc origin.

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~ 5

■ suffix forming nouns:

1》 such as sampler . Compare with -ar 1 . [ending corresponding to L. -aris .]

↘such as butler , danger . [ending corresponding to L. -arius , -arium .]

↘such as border . [ending corresponding (via OFr. -eure ) to L. -atura .]

↘such as laver . See laver 2 . [ending corresponding (via OFr. -eor ) to L. -atorium .]

2》 equivalent to -or 1 .

Origin

via OFr. or Anglo-Norman Fr. (see above).

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~ 6

■ suffix chiefly Law (forming nouns) denoting verbal action or a document effecting such action: disclaimer.

Origin

from Anglo-Norman Fr. (infin. ending).

Concise Oxford English vocab.      Сжатый оксфордский словарь английского языка.