The term 'CERTAIN WIND' can be broken down into three crossword solutions: REED (4 letters), EASTERLY (8 letters), and WESTER (6 letters). A REED is a type of tall grass that grows in wet areas, such as marshes. An easterly wind is a wind that blows from the east towards the west. A WESTER is a wind that blows from the west towards the east. All three of these winds are considered to be certain winds because they are predictable and consistent.