1. Literally, a solution used to cleanse the eyes of contaminants. The professor was quick to administer eyewash to the student who was splashed with chemicals during the experiment.
2. Nonsense or foolishness. His explanation is total eyewash and doesn't answer the question at all.
eyewash
1. n. nonsense; deception. It’s not eyewash! It’s true!
2. n. liquor. You’ve been putting away a lot of that eyewash, haven’t you?