The word hypotensive refers to therapeutic agents - including natural substances such as herbs, oils, or essences, or conventional pharmaceutical drugs, that lower (reduce) blood pressure.
'Hypotensive' is generally easy to remember in this context due to its similarity to the word 'hypotension' - which is the medical condition of low blood pressure.
Hypotension is the opposite of hypertension.
Hypotension may occur for a variety of causes, including excessive fluid loss, e.g. due to burns, diarrhoea or vomiting, or blood loss - either within the body or external blood loss.