Combining paste() and expression() functions in plot labels

An alternative solution to that of @Aaron is the bquote() function. We need to supply a valid R expression, in this case LABEL ~ x^2 for example, where LABEL is the string you want to assign from the vector labNames. bquote evaluates R code within the expression wrapped in .( ) and subsitutes the result into the expression.

Here is an example:

labNames <- c('xLab','yLab')
xlab <- bquote(.(labNames[1]) ~ x^2)
ylab <- bquote(.(labNames[2]) ~ y^2)
plot(c(1:10), xlab = xlab, ylab = ylab)

(Note the ~ just adds a bit of spacing, if you don't want the space, replace it with * and the two parts of the expression will be juxtaposed.)

Use substitute instead.

labNames <- c('xLab','yLab')
plot(c(1:10),
     xlab=substitute(paste(nn, x^2), list(nn=labNames[1])),
     ylab=substitute(paste(nn, y^2), list(nn=labNames[2])))