What does the suffix dia mean?

The suffix "-dia" doesn't have a consistent meaning on its own. It's often part of a larger Greek or Latin root, and its specific meaning depends on the whole word.

Here are some examples:

* -dia- in Greek: Often indicates "through, across, between"

* Diameter: "through the measure" (the distance across a circle)

* Diagnosis: "through knowing" (the identification of a disease)

* Diaphragm: "partition across" (the muscle separating the chest and abdomen)

* -dia- in Latin: Can indicate "day"

* Diurnal: "daily"

* Diary: "daily record"

However, "-dia-" can also be part of words with a completely different origin. For example:

* Diamond: This word comes from the Greek word "adamas", meaning "unconquerable".

* India: This word comes from the Indus River, not from a Greek or Latin root.

Therefore, when trying to understand the meaning of a word ending in "-dia", it's essential to consider the entire word and its etymology.