'antitrust-related' originates from the compound of 'antitrust' (a U.S. legal/business coinage from the late 19th century formed from the prefix 'anti-' + 'trust') and 'related' (the past participle/adjective from 'relate', ultimately from Latin 'relatus'), where 'anti-' meant 'against' and 'trust' referred to a business 'trust' or monopoly.

'antitrust' was coined in American English in the late 1800s to describe opposition to large corporate 'trusts' (combinations of companies). 'Related' derives from Latin 'relatus' (via Old French/Latin into Middle English) becoming the verb 'relate' and its adjective/past participle 'related'. The modern compound 'antitrust-related' arose by combining these contemporary English elements to describe matters connected to antitrust.

Initially 'antitrust' specifically signified being opposed to business trusts or monopolies; over time the compound 'antitrust-related' evolved to mean more generally 'connected with antitrust law, enforcement, policy, or issues' rather than merely 'against trusts'.