(chemistry) A functional group that is in close proximity to another that is taking part in a reaction; especially such a functional group that affects the rate or outcome of the reaction

(chemistry) An atom or group that is detached from the rest of a molecule during a reaction.

(marketing) The primary group of people that something, usually an advertising campaign, is designed to appeal to.

A front organization that appears to be an independent voluntary association or charitable organization.

Alternative spelling of demogroup

(computing) A set of users grouped together on a system for administrative purposes. / (computing) A community of users of a particular machine, operating system, etc.

(graphical user interface) A rectangular control that can contain other controls, intended for grouping similar items visually.

Alternative spelling of headgroup

An advocacy group.

(taxonomy) A monophylum