Heterogenous chunks served around or below room temperature are a salad. To be heterogenous, there must be at least two different things, so... two is the minimum, dressing doesn't count towards the total.
Cucumber slices with tajΓn? Not a salad.
Cucumber, tomato, and red onion dressed with tahini? Jerusalem salad.
Tuna mixed with mayonnaise? Not tuna salad.
Tuna mixed with celery and mayonnaise? Tuna salad (barely).
Lime jello? Not a salad.
Lime jello cut into cubes mixed with orange jello cut into cubes? Jello salad.
Cranberries stewed with spices and sugar? Not a salad, cranberry sauce.
Cranberry sauce mixed with mandarin oranges, cut pineapple, and walnuts, set into a bundt-shaped jello mold? Cranberry salad.