IPA: /ˈstræɡlər/
KK: /ˈstræɡlər/
A person who is slow to keep up with others, often falling behind in a group or activity.
During the hike, the straggler lagged behind the rest of the group.
Straggler → It is formed from "straggle" (from the Middle English *straglen*, meaning to stray or wander) and the suffix "-er" (meaning a person who). A straggler is a person who strays or wanders away from the main group.
Think of someone who is 'wandering' or 'straying' from the group — that's why a straggler is someone who is left behind.