Student or Learner
The Vandy took a coil of rope from his hands. Cal had been waiting for us at the pond. When he’d seen me, he’d given me a barely perceptible nod, which was the Cal version of waving his hands over his head and yelling, “Hey, Sophie!”
Cal usually waves his hands over his head and yells "Hey Sophie!" but now he'd given me a barely perceptible nod?
Cal is not a demonstrative person.
This is the way he usually greets Sophie - not with a big wave a cheery 'hello'.