The noun perspiration has 2 senses (first 1 from tagged texts)
1. (5) perspiration, sweat, sudor -- (salty fluid secreted by sweat glands; "sweat poured off his brow")
2. perspiration, sweating, diaphoresis, sudation, hidrosis -- (the process of the sweat glands of the skin secreting a salty fluid; "perspiration is a homeostatic process")