Anatomy & Morphology
Small in size, many are about the size of a ten year-old Human. Goblins tend to have thick skin creating calluses, but are also able to squeeze through awkward and tight spaces. - Cats don't have a rigid collarbone which lets them slink into various shaped spaces.
Something something about being very interested in going fast and preferring to be in motion when not asleep.
Large eyes to allow them to see in the dark or at night. Nictating lids to help filter bright lights out.
Ears allowing for hearing, also leads to sensitivity to loud noises - combined with the fondness for large explosions, this tend to result in individuals developing hearing difficulties.
Biology
Goblin children are generally fond of climbing on anything and anyone, and are often found clinging to the back of their parental figure or older siblings.
Generally considered adults at age fifteen, Goblins are usually at full height a year later.
Unlike many people in their societies, goblins are strictly vegitarian. Meat consumption is not abstained out of personal or cultural preferences, but out health concerns. Stories have been told describing meat-eating goblins growing in size, temper, and brutality, leading to the individual becoming a monster referred to as a HobgoblinFindAnotherNameLater.
Most who have eaten meat (out of desperation or curiousity) find themselves becoming violently ill. The ones who survive either never touch the stuff again, or crave more meat and grow into a HobgoblinStillNeedAnotherNameLyraine-like monster who often needs to be chased out of town and later on tracked down to put out of misery.
Society
Goblins tend towards a hierarchical social structure - the head of families or communities are generally individuals who can keep the rest in line, but also host festive events for "controlled chaos" outlets. This does not always mean the leaders are the biggest, nor the meanest individuals around.
Mother-figures tend to be the most ill-tempered when dealing with others while raising children, but also prefer to not delegate parental duties beyond the individuals who are the parental roles. Some unlucky goblin scholars have speculated this cultural mindset came from a time when survival was harder, and families had to care for their own over their community and be suspicious of people outside their immediate family.
Those particular scholars have difficulties when among their fellow goblins - particularly ones who are raising kids.
Beyond raising children, their social structure is based on maintaining structure and satiating curiousity. And bonfires.
Due to big ears + explosions + inconsistent foresight = goblin language being a sign language?
History of the Species
Insert myth of being crafted by gods here.
Several cultures have attributed benign ill-luck to upsetting a goblin or a group of goblins. In such circumstances, usually the "victim" finds themselves inconvenienced through a sequence of carefully arranged events.
Goblins have an affinty for fire, and when combined with their curiousity, they tend to create new ways of causing tempers and inventions to detonate. Several regions have local laws banning the presence of a goblin near the more dangerously flamable/explosive materials - though abiding by said laws are another matter.
I said - stop stabbing me!
Beauty Ideals
In general, Goblins find beauty in others who can craft or demonstrate feats of fine dexterity - this could be fine mechanical work, embroidery, elaborate lockpicking, or quick reactions to sudden changes. A goblin who is known as "clumsy" is more likely to struggle with finding a romantic partner among other goblins, and one who has many burn or other scars could also be seen as "slow to react" or "careless."
Taboos
While the absence of scars is preferred, there is also the general preference to find partners who are less likely to avoid working for goals.
Don't tie a goblin down with weights, it messes with their sense of movement and speed. something Something, this is more as taboo as a result of it's physically uncomfortable.
Eating meat.
"Ears allowing for hearing, also leads to sensitivity to loud noises - combined with the fondness for large explosions, this tend to result in individuals developing hearing difficulties." - I like them already! <3
Every default image of a goblin has large ears for better hearing, but if I combine it with a fondness of explosions and add in a dash of recklessness ... well, hearing loss is a thing. Maybe the "Goblin" language is a sign language? [I]Lyraine skitters off to make this note
that would be a perfect match, me thinks!