A trophic level is a stage in a food chain.
Now you know that Trophic means nutrition, then trophic level must mean nutrition level.
The first trophic level is always a producer (plant).
In this example of a food chain the first trophic level is the oak tree. The second trophic level is the caterpillar and the third trophic level is the treecreeper (small bird). The hawk would be the fourth trophic level in this food chain.
For producer, primary consumer, secondary consumer and tertiary consumer follow the links.
The first trophic level is the producer in a food chain, this is usually a plant.
Examples include: Algae, Grass and trees
The second trophic level is the primary consumer in a food chain, this is usually a herbivore.
Examples include: caterpillars, cows, locusts, rabbits, tadpoles and shrimp
The third trophic level is the secondary consumer in a food chain, this is either a carnivore or an omnivore.
Examples include: frogs, crabs, black birds, foxes and badgers
The forth trophic level in a food chain is the tertiary consumer, this is usually a carnivore but may sometimes be an omnivore.
Examples include: hawks, humans, great white sharks and bears