1. A young fish, especially a salmon or trout, in its earliest stage after hatching and before it becomes a fry.
Usage: ichthyology; primarily used in fish farming and aquaculture

Examples

• The hatchery released thousands of alevins into the river to boost the salmon population.
• Alevins remain attached to their yolk sacs for several weeks after hatching.
• Fish farmers carefully monitor water conditions to ensure the alevins develop properly.
• Once the alevin absorbs its yolk sac, it becomes a fry and begins to feed independently.
• The alevin stage is critical for the survival of young trout in cold-water streams.