met ‧ i ‧ er /ˈmetieɪ,ˈmeɪ- $ meˈtjeɪ,ˈmetjeɪ/ BrE AmE noun [countable usually singular]
[ Date: 1700-1800 ; Language: French ; Origin: métier , from Vulgar Latin misterium , from Latin ministerium 'work, ministry' ]
formal someone’s metier is the type of work or activity that they enjoy doing because they have a natural ability to do it well:
Acting is not my metier.