A binary language belongs to $\mathrm{EXPTIME}$ if a deterministic Turing machine decides membership within $2^{p(n)}$ transitions on every input of length $n$, for some polynomial $p\in\mathbb{N}[X]$. The machine is the finite elementary single-tape machine defined here: input bits are distinct from blank, input appears in its original order, and each transition performs one move or one write. A terminal state's Boolean label gives the answer. The polynomial in the exponent may have any fixed degree; this is the usual EXPTIME, also called EXP.