The definition of preachy is someone who likes to excessively teach moral lessons.
An example of someone preachy is a vegetarian who talks about animal cruelty throughout the meal in an annoying way.
Inclined or given to tedious and excessive moralizing; didactic.
(comparative preachier, superlative preachiest)
- Tending toward excessive moralization.
- My old fussbudget aunt had a very preachy manner and would prattle on about the dangers of alcohol and other vices.