Meaning of -AR in English

-AR

~ 1

■ suffix

1》 (forming adjectives) of the kind specified: molecular.

2》 forming nouns such as scholar . Compare with -er 5 .

Origin

from OFr. -aire , -ier , or from L. ~is .

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~ 2

■ suffix forming nouns such as pillar .

Origin

via OFr. from L. ~e (neut. of ~is ).

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~ 3

■ suffix forming nouns such as bursar .

Origin

from OFr. -aire , -ier , or from L. ~ius , ~ium .

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~ 4

■ suffix alteration of -er 1 , -or 1 (as in liar ).

Concise Oxford English vocab.      Сжатый оксфордский словарь английского языка.