I was told that in Tanya, Chapter 42, "sin of youth" is a euphemism for wasting seed. How true is this statement? (Sources, please.)
There is a soul that is of lowly nature and origin, coming from the lower gradations of the Ten Sefirot of Asiyah, which cannot discover G‑dliness by contemplation except with difficulty and forcefulness, especially if it had been contaminated by the sin of youth, for the sins interpose,... (as is explained in Sefer Chasidim, ch. 35).
[Quotation from Chabad.org, emphasis mine.]
If not, then what does "sin of youth" mean in Tanya?
(And if different then in Tehillim (above) what does it mean in the Tehillim?)