  We explore the wind-driving mechanism of giant stars through the nearby (117
pc), intermediate-luminosity ($L \approx 1600$ L$_\odot$) star EU Del (HIP
101810, HD 196610). APEX observations of the CO (3--2) and (2--1) transitions
are used to derive a wind velocity of 9.51 $\pm$ 0.02 km s$^{-1}$, a
$^{12}$C/$^{13}$C ratio of 14 $^{+9}_{-4}$, and a mass-loss rate of a few
$\times$ 10$^{-8}$ M$_\odot$ yr$^{-1}$. From published spectra, we estimate
that the star has a metallicity of [Fe/H] = --0.27 $\pm$ $\sim$0.30 dex. The
star's dusty envelope lacks a clear 10-$\mu$m silicate feature, despite the
star's oxygen-rich nature. Radiative transfer modelling cannot fit a wind
acceleration model which relies solely on radiation pressure on condensing
dust. We compare our results to VY Leo (HIP 53449), a star with similar
temperature and luminosity, but different pulsation properties. We suggest the
much stronger mass loss from EU Del may be driven by long-period stellar
pulsations, due to its potentially lower mass. We explore the implications for
the mass-loss rate and wind velocities of other stars.
