Antonyms for the term "Endothelial Growth Factors" would include terms related to suppression, inhibition or stunting of growth. This might include words like "inhibitors", "suppressors", or "anti-growth factors". It could also encompass terms related to the opposite of growth, which might include words like "decay", "degeneration", or "atrophy". Overall, the term "antonyms" refers to words that are opposite in meaning to the original term, and in the context of endothelial growth factors, this would refer to terms that describe things that reduce, inhibit, or prevent growth rather than promote it.