Deut. 32:20 and Hab 2:4 both contain the Hebrew word emun (Heb: אמון), translated in the KJV as "faith." Emun is H529 in Strong's where it's defined as "faithfulness, trusting."
However, the word emun derives from the root word aman (Heb: אמן), which is a very common word in the Bible. Aman is strong's H539 where it's defined as: "to support, confirm, be faithful." Emun may only appear twice, but the root aman "occurs 108 times in 102 verses" in Tanakh.
In translation, "belief," "support," "sturdy" and "faith" are read as being different words, but in the original Hebrew they all derive from the same root.
"Faith" usually implies commitment and trust in a way that isn't implied by "belief." From the context in Deuteronomy and Habakkuk, "faith" seems to be a more accurate translation for emun than "belief."