NATO is adopting gender-neutral language at its highest military level, changing the job title of the alliance's most senior officer.
Air Chief Marshal Sir Stuart Peach will now be known as 'Chair' rather than 'Chairman' of the military committee.
The alliance said Air Chief Marshal Sir Stuart is a "strong supporter of removing barriers to the integration of women, not only in the armed forces, but across all levels of leadership".
Air Chief Marshal Sir Stuart, a former UK Chief of the Defence Staff, has been Chair of NATO's military committee since 2018 and is the first Briton to hold the position for 25 years.
On Twitter, the UK Delegation to NATO said the move had been implemented to "promote inclusivity".
Air Chief Marshal Sir Stuart's role includes advising NATO Secretary General Jens Stoltenberg and the North Atlantic Council on defence matters and strategy.
He acts in an international capacity within the committee - which also advises NATO's Defence Planning Committee and Nuclear Planning Group.
Future successors to Air Chief Marshal Sir Stuart within NATO will also take on the gender-neutral title.
Last year, the RAF Gender Network was launched and hosted several webinars on gendered language and organisational change.
In October, the Air Force announced it is promoting the use of gender-neutral pronouns to encourage inclusion and diversity across the service.
Alternative pronouns to 'he', 'she', 'him' and 'her' include 'Ze', 'Per' and 'Hir'.
Past language systems within the force could have seen female officers referred to as 'Sir'.
Cover image: Exterior of NATO's headquarters in Brussels (Picture: NATO TV).