Avocado is not classified as a tree nut, and people who suffer from nut allergies can usually enjoy avocados without experiencing any adverse reactions.
Rather than a nut, the avocado is classified as a berry, in the fruit family. But it is common for people to mistake avocados for a vegetable, nut, or drupe.
Some people are allergic to avocados, but this type of allergy is usually separate from nut allergies, which are caused from a wide range of nuts from peanuts to cashews.
Allergy to avocado is linked more closely to latex allergies, and people who suffer from an allergy to latex sometimes have a similar reaction to avocados.