“Sill” in Japanese
Short answer
Sill in Japanese is “敷居” (shikii). Full meaning: threshold (esp. one with grooves for sliding doors), sill.
Other ways to say “Sill” in Japanese
蹴放し
kehanashi threshold (lacking the grooves needed for a sliding door), sill
しきい
shikii threshold (esp. one with grooves for sliding doors), sill
じきい
jikii threshold (esp. one with grooves for sliding doors), sill
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