Straggle
/ˈstræɡl/
Definition 1 of 2
Pro Tip 1/3Slow Movement
Use 'straggle' to describe someone moving slowly without purpose compared to others. 
The children straggled behind, fascinated by street performers.
Pro Tip 2/3Irregular Formation
Use when people or animals are not moving in a structured or organized way. 
The ducklings straggled along behind their mother.
Pro Tip 3/3Not Just Distance
'Straggle' implies both physical distance and a scattered or casual manner. 
After the run, the joggers began to straggle in at different times.