Spawn refers to the ability of someone or something to appear or "come to life". In Tibia (or other games) it refers to the ability of creatures, items or players to appear at a certain time.
Player Spawn
In Tibia all players
Creature Spawn
In Tibia almost all monsters respawn at a certain rate or randomly on the game world in specific places. However, some monsters may only spawn as an event triggered by a player doing a quest.
Please note that creatures will not appear if you are close to it's spawning location. Some Demon spawns however, will spawn even if you are close to them.
The rate at which creatures spawn is determined also by the amount of online players. The spawning rate is faster if there are many players and slower if there are few players.
Creature Raids
Creatures in raids will spawn on their pre-defined spawning places even if there are players in those locations.
Random Spawning
Spawns used to be set positions, but in recent updates they have become a little random (allowing a few spaces in any direction). The most recent change was in digging scarabs; now they will spawn anywhere immediately around the spot you dig them up from.
Item Spawns
Many items in Tibia respawn after a certain period of time (like in some quests) or as daily respawns. A great percent of daily spawns is comprised of Rubbish. Some items may only spawn as an event triggered by a player when doing a quest.
Game Tokens
Some Game Tokens such as Chess, Checkers and Tic-tac-toe pieces are daily respawns and can be found in all Game Rooms on certain cities.