This might be a simple one, but I'd like to have your opinion/authoritative statements: I write a thesis in a technical modelling context, where a mathematical model operates on a discrete set of timesteps (or time steps?). Paramaters/Variables that are defined over this set are then called timeseries (or time series?).
A Google battle yields the one-word expressions as clear victors, but dict.leo.org does only like the two-word expressions. So which one is to be preferred? Or is there even a difference in meaning between both variants?
Conclusion: after a temporary confusion from a third option "time-step", I settled for the two word versions for both words.