  We present systematic measurements of azimuthal anisotropy for strange and
multistrange hadrons ($K^{0}_{s}$, $\Lambda$, $\Xi$, and $\Omega$) and $\phi$
mesons at midrapidity ($|y| <$ 1.0) in collisions of U + U nuclei at
$\sqrt{s_{NN}} = 193$ GeV, recorded by the STAR detector at the Relativistic
Heavy Ion Collider. Transverse momentum ($p_{\text{T}}$) dependence of flow
coefficients ($v_{2}$, $v_{3}$, and $v_{4}$) is presented for minimum bias
collisions and three different centrality intervals. Number of constituent
quark scaling of the measured flow coefficients in U + U collisions is
discussed. We also present the ratio of $v_{n}$ scaled by the participant
eccentricity ($\varepsilon_{n}\left\lbrace 2 \right\rbrace$) to explore system
size dependence and collectivity in U + U collisions. The magnitude of
$v_{2}/\varepsilon_{2}$ is found to be smaller in U + U collisions than that in
central Au + Au collisions contradicting naive eccentricity scaling.
Furthermore, the ratios between various flow harmonics ($v_{3}/v_{2}^{3/2}$,
$v_{4}/v_{2}^{4/2}$) are studied and compared with hydrodynamic and transport
model calculations.
