\begin{definition}[Definition:Calendar/Julian/Year]
A '''Julian year''' is the length of a year as defined using the '''Julian calendar'''.
:$1$ '''Julian year''' $= \begin{cases} 366 \, \text {days} & : 4 \divides y \\
365 \, \text {days} & : 4 \nmid y \end{cases}$
where:
:$y$ denotes the number of the year
:$4 \divides y$ denotes that $y$ is divisible by $4$
:$4 \nmid y$ denotes that $y$ is not divisible by $4$.
\end{definition}