[Note from moderator: This is not on topic, so no discussion please, but the poster may send one digest of responses.] Hello, I'd like to know who uses the spelling "equalizer" and who uses "equaliser". In English overall, the suffix "-ize" is catching on and displacing "-ise"[^note], and such Americanisms dominate scientific writing even more than most other fields. On the other hand, "-ise" remains especially common in Australia, and there sure are a lot of Australian category theorists, aren't there? While I probably don't need Americans confirming the use of "equalizer", I'd be interested to hear what people in other countries do (or any Americans who use "equaliser"), or anyone who uses "-ise" normally but adopts "equalizer" as a technical spelling (or the reverse), or anyone who distinguishes "equalizer" from "coequalizer" (that would be weird) or any other usage of both forms, or if you have useful information about this besides your own practice. (The disjunction "or" here is non-idempotent, like the multiplicative \par in linear logic, multiset sum, disjoint union of sets, etc; the more criteria you meet, the more I want your response.) If you want, you can look at <https://en.wikipedia.org/wiki/Talk:Equaliser_%28mathematics%29> for a discussion of this issue that suffers from a lack of data. --Toby Bartels [^note]: That is, when it is the suffix derived from Greek "-izein" or patterned on it; "-ise" is used even in the U.S. for other words, such as "advertise" and "exercise", in which it is not actually a suffix (and the less said about "-lyze", the better). [For admin and other information see: http://www.mta.ca/~cat-dist/ ]