rename variables in r

my_data %>% 
  rename(
    sepal_length = Sepal.Length,
    sepal_width = Sepal.Width
    )

library(plyr)
rename(d, c("beta"="two", "gamma"="three"))
#>   alpha two three
#> 1     1   4     7
#> 2     2   5     8
#> 3     3   6     9

# df = dataframe
# old.var.name = The name you don't like anymore
# new.var.name = The name you want to get

names(df)[names(df) == 'old.var.name'] <- 'new.var.name'