inset
noun
• a thing that is put in or inserted.
• "a pair of doors with their original stained-glass insets"
inset
verb
• put in (something) as an inset.
• "washbasins are usually inset into a toilet table to form a vanity unit"
INSET
noun
• training during term time for teachers in British and South African state schools.
• "a heavy investment in INSET is needed"
Origin:
1970s: acronym from in-service education and training .