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tokens: are dominated by dark matter halo once one goes sufficiently far out in the galaxy. What is relevant is that the halo is dense and compact and hence the dark matter dominates even at inner radii as in LSBs (e.g. Ghosh Jog 2014 ) or in dwarf galaxies like DDO 168 (Ghosh Jog 2018 ). It is this feature that influences the development of a slow bar due to dynamical friction. DDO 168 has a high central dark matter density, ρ 0 = (39.81 ± 6.37) × 10 −3 and a scale radius, r s = 2.81 ± 0.83 kpc for an isothermal dark matter halo (Oh et al. 2015 ). It has been found that the dark matter halo dominates the observed dynamics of this galaxy starting from the central region (Ghosh Jog 2018 ). Thus, the detection of a slow bar in DDO 168 supports the proposition that the dense, compact dark matter halo slows down the bar through dynamical friction. We note that all the three galaxies that so far have been seen to host an H i bar (NGC 2915, NGC 3741, and DD0 168), also have the property that the bar is slow. We further note that the H i gas is very extended (several times the optical radius) in all three galaxies, and in NGC 3741 and DDO 168 the halo is dense and compact (Ghosh Jog 2018 ). Here, it should be emphasized that now, there is evidence that slow bars are more common than what was thought before. For example, using an innovative and simple technique, Font et al. ( 2017 ) determined the corotation radius in 68 galaxies. Using the photometric data, they further determine the bar length in these galaxies and consecutively estimate the to find that almost one-third of their sample galaxies host ‘slow bars’ (i.e. ). This commonality of slow bars in galaxies can be thought of due to more effective braking by the dark matter halo than what was believed before. However, the status of the pattern speeds in dark matter dominated galaxies, especially LSBs, is not well studied as compared to the HSBs (Font et al. 2017 ; Peters Kuzio de Naray 2019 ). As shown in our works for DDO 168 and NGC 3741, the dense and compact halo might play an import role in slowing down the H i bars. Thus, though the braking of bars by dark matter halo is more common, yet the dark matter dominance from the central region might have an enhanced effect in determining the slowdown of the bar. Further, Font et al. ( 2014b ) have shown by simulation that, due to the dynamical braking by the dark matter halo, the corotation radius moves outwards, at the same time, the bar can also grow in length significantly due to accretion. This implies, even for a slow bar the ratio, can settle well below the nominal value of 1.4, thus declaring the bar to be a fast one. Hence, all the fast bars as decided by criteria might not be fast ones. However, we clarify that the traditional definition of a slow bar (i.e. ) does not change our conclusion on the existence of the slow bar in DDO 168, albeit it puts questions on its rarity. 4 CONCLUSION We have identified an H i bar in the dwarf galaxy DDO