-ier

-ier

suffix forming nouns
a variant of -eer: brigadier.
[from Old English -ere -er1 or (in some words) from Old French -ier, from Latin -ārius -ary]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

-ier1

,
var. of -er 1 , usu. in nouns designating trades: collier; clothier; furrier; glazier.
[Middle English -ier(e), variant of -yer(e) (compare -yer)]

-ier2

,
a noun suffix occurring mainly in loanwords from French, often similar in meaning to -eer, with which it is etymologically identical (brigadier; financier); it is also found in an older group of loanwords with stress on the initial syllable (barrier; courier) and in more recent borrowings without the final r sound (dossier; hotelier).
[< French, Old French < Latin]
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