What does CkC mean in chemical bonding?

I'm working on a chemistry question where I'm supposed to use average bond energies to estimate enthalpy changes for a reaction. It gives me these bond energies to work with:

\begin{align} \ce{C-H}&=&413\\ \ce{C-C}&=&348\\ \ce{C-Br}&=&276\\ \ce{H-Br}&=&366\\ \ce{CkC}&=&614\\ \end{align} I know how to do the question, but I don't what $\ce{CkC}$ is. I can't find it online or in my textbook. What does the "k" mean?

• Which text book did you find this notation in? The info will help future visitors having similar problem. – Gaurang Tandon Mar 24 '18 at 13:08

$\ce{C=C}$ average bond energy is somewhere around $\pu{614 kJ/mol}$ so "k" probably indicates a double bond