Irregular plurals of classical loanwords (-a, -ums)

Academic vocabulary

When discussing science and research, you will encounter many classical loanwords. Some take regular Dutch plural endings, like het congres (the conference), which becomes congressen.

Classical plurals: -um becomes -a

Many academic words in Dutch end in -um. Instead of adding a standard -en or -s for the plural, the -um ending often changes to -a:

• het symposium becomes symposia
• het criterium becomes criteria
• het medium becomes media

The choice between -a and -s

For several common words, Dutch allows two correct plurals: the classical -a or the regular -s. In formal writing or academic contexts, the -a ending is often preferred.

• het museum: musea / museums
• het centrum: centra / centrums

Stages, labs, and decades

This pattern applies to many other words you will hear at academic conferences, including spaces and time periods:

• het laboratorium (the laboratory) becomes laboratoria
• het decennium (the decade) becomes decennia
• het podium (the stage) becomes podia