Does the medical suffix -us mean pertaining to?

No, the medical suffix "-us" generally doesn't mean "pertaining to". It's more commonly used to indicate:

* Masculine gender: For example, "virus" (a malevolent agent)

* Singularity (singular form): For example, "fungus" (one fungus)

While some words ending in "-us" might imply a connection to something, it's not the primary meaning of the suffix.

Here are some examples of suffixes that mean "pertaining to":

* -al: Neural (pertaining to nerves)

* -ar: Vascular (pertaining to vessels)

* -ic: Cardiac (pertaining to the heart)

* -ical: Surgical (pertaining to surgery)

* -ous: Venous (pertaining to veins)

* -tic: Diabetic (pertaining to diabetes)

It's important to consider the entire word and its context to understand its meaning.