Rare, but attested: ‘to furnish with or build a sill’.
Definitionen
To provide with or build a sill; to set on a sill. The workers carefully silled the new window opening to ensure a level base.
Synonyme
fit out
furnish with a sill
Used attributively (e.g., "sill plate") to describe something related to or situated at a sill.
Definitionen
Situated at, relating to, or forming a sill (used before another noun). The carpenters installed the sill plate before raising the wall studs.