The category of your topic (a "classification"), and one unique feature.
TOPIC+BE+CATEGORY+UNIQUE DETAIL
| TERM | is/are | CATEGORY | LINK | are more or less unique in some way |
|---|---|---|---|---|
| Crabs | are | large crustaceans | which | walk sideways |
| Dogs | are | domestic animals | that | were bred from wolves |
| "Dog" | refers to | domestic animals | which were | bred from wolves |
| Akita | is a kind of | Japanese Dog | , | made famous by Hachiko. |
| Happiness | is a form of | emotional state | caused by | eating chocolate |
| Happiness | can be defined as | an emotional state | which results from | eating chocolate |
| The word "dreich" | is a | Scottish term | which describes | cold, grey, dark, miserable weather. |
| Happiness | is defined here as | the emotional state which results from eating chocolate |
| Happiness | is here used to mean | a score of 5 or higher on the self-assessment Satisfaction scale |
| Happiness | is operationalised as | balance between positive and negative emotion (Ryff, 1989) |
Look at the first sentence of any Wikipedia article - it is a definition.
| topic | +BE | CATEGORY | CONNECT | UNIQUE POINT |
|---|---|---|---|---|
| Gold | is a | chemical element | with | symbol Au and atomic number 79. |
| Paper | is a | thin material | produced by | pressing together moist fibres of cellulose pulp |
| Economics | is the | social science | that | describes the factors that determine the production, distribution and consumption of goods and services. |
1) "Define" does not mean "copy a definition from a dictionary". Do you own research if you have to, and write your OWN definition.
2) Don't define in a boring way. We know what gold is. We know what paper is. Your unique detail must be something we don't know.