What does a Template mean by Hit Dice?

Question

If a template references Base Creature Hit Dice(For Special abilities and such.), What exactly does it mean. Does it only count for Hit dice that are given via Race(Ex. Gnolls 2 racial hitdice) or does it count HD gained from class levels(Eg a Gnoll's 2 HD +3 HD from Class Levels.). Because if its the first one then templates are largely useless for races like Human.

For Example a Human who is a Level 4 Ranger has 4 HD and also has the Pseudonatural Template. Does the human ranger gain Acid and Elec Resist 5 and DR 5/magic.

If you provide an answer a book and page number would also help and be apreciated.

Answer 1

Unless it specifies "racial hit dice", use the sum of the creature's racial HD, its class levels (or even "bonus HD" in case of things like Animal Companions) to determine the creature's total number of HD.

This definition is somewhat scattered, but see

Hit Dice: The term "Hit Dice" is used synonymously with "character levels" for effects that affect a number of Hit Dice of creatures. Creatures with Hit Dice only from their race, not from classes, have character levels equal to their Hit Dice.

on page 181 of the Player's Handbook.

Hit Die/Dice (HD): In the singular form, a die rolled to generate hit points. In the plural form, a measure of relative power that is synonymous with character level for the sake of spells, magic items, and magical effects that affect a certain number of Hit Dice of creatures.

on page 309 of the Player's Handbook.

Much of it is also inferred from usage, such as in monster entries (Look at the Troll Hunter, Monster Manual page 247).