Is tiniest a past tense word?

No, "tiniest" is not a past tense word. It's the superlative form of the adjective "tiny," meaning "the smallest."

Here's why:

* Past tense describes an action that happened in the past. "Tiniest" doesn't describe an action.

* Superlative adjectives indicate the highest degree of a quality.

For example:

* Tiny (adjective)

* Smaller (comparative adjective)

* Tiniest (superlative adjective)