Toward the inside or interior; moving or directed toward the center.
From 'inward' (Old English 'inweard' meaning toward the inside) plus '-s' suffix. The word has meant the same thing for over 1,000 years.
English is almost unique in adding '-s' to directional words (inwards, onwards, towards), a quirk that confuses learners but adds a nice rhythm to how we speak about movement.
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