Glossary of academic publishing terms

Short definitions of the terms that decide where you publish. Figures are drawn from the same 11,447-journal dataset the rest of the site runs on, and every entry links to where the term is used in context.

APC (Article Processing Charge)

A fee charged by a journal to publish an accepted article, paid by the author, their institution or their grant rather than by a reader. It is the standard revenue model for fully open-access journals, and an optional extra in hybrid subscription journals. Charges vary by roughly an order of magnitude for editorially comparable work: across the 4,496 journals in our directory that publish a figure, the median is $3,140 and the maximum is $12,690. A further 1,290 journals record no charge at all.

See: APC finder · What it costs to publish · How institutions cover APCs

Impact Factor

The average number of citations received in one year by articles a journal published in the previous two years. It is calculated by Clarivate from the Web of Science database and published in Journal Citation Reports, so it is a proprietary product and journals outside Web of Science do not have one. Because citation distributions are heavily skewed, the mean sits well above what a typical article receives, which is why it is a poor proxy for the quality of any single paper. We do not publish Impact Factors.

See: Impact Factor vs h-index vs CiteScore · What metrics we publish, and why

h-index

A journal or author has an h-index of h when h of its items have each been cited at least h times. It resists distortion by a single highly cited outlier, but it is cumulative and can only rise, so it reflects age and volume as much as current quality. The median across our directory is 26. We show it as an OpenAlex citation statistic and explicitly not as a quality verdict.

See: What h-index actually measures · Journal directory

CiteScore

Elsevier's journal metric, computed from the Scopus database as average citations per document over a four-year window. The longer window makes it steadier than the two-year Impact Factor and fairer to slower-citing fields, and its methodology is published rather than proprietary. It remains a mean over a skewed distribution, so it says little about any individual article.

See: Comparing the three metrics · What Scopus indexing means

ISSN

The International Standard Serial Number, an eight-digit identifier issued by a national ISSN centre and recorded in a public register. Print and electronic editions of the same journal receive different ISSNs, so two numbers is normal. Because the register is public and independent of the journal, an ISSN is the fastest way to confirm that a title exists as it claims — every journal in our directory has at least one verified ISSN.

See: How to verify an ISSN · Journal check

DOAJ

The Directory of Open Access Journals, an independent, community-curated index of open-access journals. Listing requires an application in which the journal discloses its editorial board, peer review model, licensing and publication charges, so a DOAJ record is primarily evidence of disclosure rather than a quality audit. 3,620 of the journals we track have a full DOAJ record, which is the source of most editorial metadata on our journal pages. DOAJ does not list subscription journals, so absence proves little on its own.

See: What DOAJ listing means · Our data sources

Predatory publishing

A loose term for journals that charge publication fees while providing little or none of the editorial service they advertise — typically no genuine peer review, fabricated or unwitting editorial boards, fees disclosed only after acceptance, and no archival preservation. The label is contested because it is applied inconsistently and can follow a journal long after it changes hands. We do not label individual journals; we publish the verifiable facts and let the pattern speak.

See: The seven-step verification check · Journal check · Why we publish no blacklist

Beall's List

A list of “potential, possible, or probable predatory” open-access publishers compiled by the University of Colorado librarian Jeffrey Beall, and the best-known attempt to name such journals. Beall took it offline in 2017 following sustained legal pressure from publishers it named, though unofficial mirrors persist. It illustrates the durable problem with blacklists: they age badly, they are one person's judgement, and a listed name follows a journal even after its practices change.

See: Why we do not publish a blacklist · Our position

Plan S / cOAlition S

An initiative launched in 2018 by a coalition of national and charitable research funders requiring that publications from the research they fund be openly available immediately on publication, with no embargo and under an open licence — normally CC BY. It binds researchers through their grant conditions rather than through publishers. Compliance can be met by publishing in an open-access journal, by depositing in an open repository, or via a qualifying transformative agreement.

See: Plan S compliance checklist · Transformative agreements

Sherpa Romeo

A free service, run by Jisc, that records publishers' policies on self-archiving: which version of a paper you may deposit — submitted, accepted or published — in which kind of repository, under what licence, and after what embargo. It is the standard place to check before relying on green open access, since the terms differ by publisher and often by journal.

See: Embargo period · Meeting funder requirements · Green open access

Embargo period

The delay a publisher imposes between an article's publication and the point at which an author may make a copy openly available in a repository. Embargoes commonly run from six to twenty-four months and vary by publisher, journal and article version. They matter because funders operating immediate-access policies, including Plan S funders, do not accept an embargoed route as compliant.

See: Sherpa Romeo · Plan S compliance · Preprint

Preprint

A manuscript posted publicly on a preprint server — such as bioRxiv or medRxiv — before or during peer review. Preprints establish priority, allow early feedback and make results available immediately, and most journals in biomedicine now permit them, though policies vary and should be checked before posting. A preprint has not been peer reviewed, and citing one means citing unreviewed work.

See: Peer review · How long peer review takes

Peer review (single-blind, double-blind, open)

Evaluation of a submitted manuscript by independent researchers in the field before publication. In single-blind review the reviewers know the authors' identities but not vice versa; in double-blind review neither side is told, which reduces bias related to author identity and institution; in open review identities are disclosed and sometimes the reports are published alongside the article. Genuine review takes weeks — among the 3,620 journals reporting a figure, the median time to publication is 14 weeks — so advertised acceptance in days indicates the absence of review rather than efficiency.

See: How long peer review takes · Being suspicious of speed · Journal check

Where these terms come from

Definitions here describe how these terms are used in biomedical publishing rather than reproducing any organisation's official wording. Where a term names a specific service, the authoritative definition is that service's own — see data sources for what we use and under which licence, and methodology for how the figures on this page are calculated.