Spoor is the trail a wild animal leaves behind on the ground — footprints, droppings, broken grass, anything a tracker can read to say 'it went that way, and not long ago'. The word covers the whole trail, not one single print. This is a specialist word from hunting and wildlife tracking, and it comes into English from South Africa (through Afrikaans and Dutch), so it turns up most often in writing about Africa: safari books, nature documentaries, old hunting stories. A ranger might say 'we picked up the spoor at the river' — meaning they found the trail and started following it. Two points of grammar your students will need. It is normally uncountable: you say 'fresh spoor', 'the spoor was cold', not 'a spoor' or 'three spoors'. And it also works as a verb, 'to spoor', meaning to follow that trail — though the verb is rarer, and most speakers today would just say 'to track'. Outside tracking, you will sometimes see it used figuratively in literary writing — 'the spoor of an old empire' — meaning the traces something has left behind. That is a writer reaching for a striking word; it is not everyday use.

（野生動物留下的）足跡、行蹤、蹤跡。台灣講狩獵或動物追蹤時說「獸跡」「足跡」；注意這個字是整條線索（腳印、糞便、壓倒的草都算），不只是一個腳印。