December 4, 2022

Spectrums or spectra are both accepted plurals of spectrum.

Statuses and status are both accepted plurals of status. Status is the more common of the two.

Both strata and stratums are accepted plurals of the Latin noun, stratum.

Symposium comes from Latin, and so its original Latin plural form is symposia. Over time and frequent misuse, symposiums has also become accepted as a plural.