positive [LME] At the core of positive is the idea of placing something firmly, and the ultimate source is Latin ponere ‘to place’. In the 14th century the English word was used to refer to laws as being formally laid down. From this developed the more general meaning ‘explicitly laid down and admitting no question’ (as in proof positive), and later ‘very sure, convinced’. Position [LME] comes from the same root, as does postpone [L15th] literally ‘place after’. See also compost, post.