• three-cornered

(multilateral is similar to ...) having three lobes

• three-lobed

(multilateral is similar to ...) having four lobes

• four-lobed

(multilateral is similar to ...) having five lobes

• five-lobed

(multilateral is similar to ...) having many lobes

• many-lobed

(multilateral is similar to ...) having lobes radiating from a central point

• palmately-lobed

(multilateral is similar to ...) having three sides

• three-sided
• triangular
• trilateral

(multilateral is similar to ...) having eleven sides

• eleven-sided

(multilateral is similar to ...) having ten sides

• ten-sided

(multilateral is similar to ...) having nine sides

• nine-sided

(multilateral is similar to ...) having deep bilateral lobes

• deep-lobed

(multilateral is similar to ...) having two lobes

• two-lobed

(multilateral is similar to ...) involving two parts or elements

• bipartite
• two-part
• two-way

(multilateral is similar to ...) involving both houses of a legislature

• joint

(multilateral is similar to ...) involving more than two parties

• multipartite

(multilateral is similar to ...) having four sides

• four-sided
• quadrilateral

(multilateral is similar to ...) having five sides

• five-sided

(multilateral is similar to ...) having six sides

• six-sided

(multilateral is similar to ...) having seven sides

• seven-sided

(multilateral is similar to ...) having eight sides

• eight-sided

(multilateral is similar to ...) involving three parties or elements

• three-party
• three-way
• tripartite