"I before e, except after c" is a mnemonic device used to help many students remember how to spell certain words in the English language. It means that, in words where i and e fall together, the order is ie, except directly following c, when it is ei. For example:
ie in words like siege, friend
ei in words like ceiling, receive
However, in its short form the rule has many common exceptions, such as species, science, sufficient (where ie follows c) or seize, weird, sovereignty, vein, feisty, kaleidoscope and neighbor (where ei is not preceded by c). More exceptions are listed below. Various augmentations to the rhyme have been proposed to handle these exceptions.
[edit] Exceptions
This section lists exceptions to the basic form; many will not be exceptions to the augmented forms. The word oneiromancies (studies into the meaning of dreams) breaks the rule twice, in both ways. The words deficiencies, efficiencies, sufficiencies, zeitgeist and einsteinium break the rule twice in the same way.
Another mnemonic device that takes the form of a non-rhyming sentence has been used to help students remember a list of common exceptions to the rule: "Let neither financier inveigle the sheikh into seizing either species of weird leisure." This sentence contains both "ie after c" exceptions and "e before i" exceptions.
[edit] cie
Some groups of words have cie:
Inflections of words ending -cy (fancied, policies, etc.)
science and related words (conscience, prescient, etc.)
Other words ending -cient -ciency (ancient, efficiency, etc.)
Suffixes -ier or -iety after a root ending in -c (financier, glacier, society, etc.)
[edit] ei not preceded by c
Some groups of words have ei:
Chemical names ending in -ein or -eine (caffeine, casein, codeine, phenolphthalein, phthalein, protein, etc.)
Many proper names (Keira, Breidi, Keith, Leith, Neilla, Sheila, etc.)
Scottish English words (deil, deid, weill, etc.)
Prefixes de- or re- before words starting with i (deindustrialize, reignite, etc.)
Inflection -ing after verbs those ending in e which do not drop the e (being, seeing, swingeing, etc.)
Miscellaneous others: in the following lists, words are grouped by the sound corresponding to ei in the spelling. An asterisk* after a word indicates the pronunciation implied is one of several found. Most derived forms are omitted; for example, as well as seize, there exists disseize and seizure.
[eɪ]
these exceptions are excluded by the American version: beige, cleidoic, deign, dreidel, eight, feign, feint, freight, forfeit, geisha, gleization, gneiss, greige, greisen, heigh-ho*, heinous*, inveigle*, neigh, neighbo(u)r, obeisance*, peignoir*, reign, rein, seiche, seidel, seine, sheikh*, sleigh, surveillance, veil, vein, weigh
eir as [ɛɹ] (rhotic) or [ɛə(ɹ)] (non-rhotic)
these exceptions are excluded by the American version: heir, their
[i]
these exceptions are the only ones that slip through the strictest interpretation of the British version: either*, heinous*, inveigle*, keister, leisure*, monteith, neither*, obeisance*, seize, seizin, sheikh*, specie, teiid
[i] or [ɪ], depending on happy tensing
these exceptions may slip through the British version: species
eir as [ɪɹ] (rhotic) or [ɪə(ɹ)] (non-rhotic)
these exceptions may slip through the British version: weir, weird
[aɪ]
eider, either*, Einstein, einsteinium, feisty, Frankenstein, heigh-ho*, height, heist, kaleidoscope, leitmotiv, neither*, Rotweiller, seismic, stein, zeitgeist
[ɪ]
counterfeit, forfeit, surfeit
[ɪ] or [ə], depending on weak vowel merger
foreign, reveille*, sovereign
[ɛ]
heifer, leisure*, peignoir*
[æ]
reveille*
e and i in separate segments
albeit, atheism, deify, deity, onomatopoeia
Don't ya just love the English Language? LOL