amensalism

noun Ecology.

1. a relationship between two species of organisms in which the individuals of one species adversely affect those of the other and are unaffected themselves.

1. A relationship between two organisms in which one organism is harmed or inhibited and the other is unaffected. Examples of amensalism include the shading out of one plant by a taller and wider one and the inhibition of one plant by the secretions of another (known as allelopathy). Compare commensalism mutualism parasitism.