fisonomía, physiognomy, features.
flacucho, flabby, lean, soft and weak.
flamante, flaming, brand-new.
flanco, side (of a ship).
flanquear, to flank.
flaqueza, weakness, faintness.
flaquísimo (from flaco), very lean, lank.
flojo, loose, lax; shallow; small.
flojón (aug. of flojo), lazy, good-for-nothing; más que —es, worse than good-for-nothing.