slat
noun
[ slat ]
• a thin, narrow piece of wood, plastic, or metal, especially one of a series which overlap or fit into each other, as in a fence or a Venetian blind.
• "sunlight filtered dustily through the slats of the door"
Origin:
late Middle English (in the sense ‘roofing slate’): shortening of Old French esclat ‘splinter’, from esclater ‘to split’. The current sense dates from the mid 18th century.