From Longman Dictionary of Contemporary Englishpick at something phrasal verb1 EATto eat only small amounts of food because you do not feel hungry or do not like the food Paige could only pick at her meal, forcing down a mouthful or two.2 TOUCHto touch something many times with your fingers, pulling it slightly She was picking at her skirt. → pick→ See Verb table
Examples from the Corpus
pick at • If not, she will pretend to look straight through him and pick at a plant leaf hoping he will go away.• Sometimes she picks at her fingers.• At dinner Norm had seconds of everything, but Benjy only picked at his food.• I pictured myself picking at least three hundred pounds a day and took the job.• A glow that came down over the trees, and picked at the burn, and spilled through my bedroom window.• Check for birds picking at the water.• I started to pick at them.• Mushroom picking at Wilgro Mushrooms at Wath, near Ripon. 