The wings are the types on either side of a given type (e.g., types 8 and 1 are the wings of type 9). The premise is that the wing types have an additional influence upon your type. The wings are most often used to describe variations of a type where one of the wings (i.e., preferred wing) has more of an influence than the other wing. For example, someone who identifies with type 9 can also have a preferred 1-wing (abbreviated 9w1) or 8-wing (abbreviated 9w8).

People new to the Enneagram types sometimes mistakenly assume that the preferred wing is the second most dominant type for a person, but the preferred wing is simply a preference between the types on either side. The simplest way to understand the preferred wing is that it places an individual on the circle (i.e., on the dominant type or to the right or left of it). Taking type 9 as an example:

• Someone who identifies their dominant type as 9 would place themself at point 9 when not taking wing preference into consideration.
• Someone who identifies their dominant type as 9 with a strong influence from type 1 would locate themself to the right of type 9 (9w1).
• Someone who identifies their dominant type as 9 with a strong influence from type 8 would locate themself to the left of type 9 (9w8).

Here's a free test to help determine Enneagram Type and Wing Preference.