Yes words can have more than one meaning, thus a day doesn't always mean 24 hours. If it was 24 a hour period in Genesis, then each day would have been the morning to the morning, not the evening to the morning which is a whole lot less hours than 24 hours!
A day is never twenty-four hours in the scripture. The Master plainly says that there are twelve hours in a day, (and he speaks moreover with the authority of what is written in Numbers 7). A twenty-four hour day is Roman calendar timekeeping, which includes the night, which is darkness. To force a twenty-four hour day into the Hebrew scriptures and writings is to force Greco-Roman thinking into and onto the scripture while denying what the Master says in Jhn11:9-10. Moreover Paul boldly states that the first man Adam is the one formed in Gen2:7, earthy, dust-like, who became a living soul, (1Cor15:45-47, and the second man is from the heavens, 1Cor15:47, Gen1:26-28, Psa8:3-8), while Psalm 8 expounds that the Son of Man, (the second man from the heavens according to Paul), is the one given dominion in Gen1:26-28. Therefore, according to Paul, the order of creation in the first two chapters of Genesis is not even given in chronological order: and that is no doubt because the first chapter is prophecy, and is fulfilled at Golgotha, for all the Prophets and the Torah prophesied until Yohanan, (Mat11:13), and the Master himself also says "My Father is/has been working until right now, and I work/have been working", and when he said that he said it concerning the Shabbat, showing that the true Shabbat was not yet even fulfilled when he said it, (Jhn5:17). All one needs to do is believe what Paul says in 1Cor15 and all of this argument/debate goes by the wayside.