řídký znamená v angličtina

sparse [sparser, sparsest]▼(not dense; meager)
adjective
[UK: spɑːs] [US: ˈspɑːrs]

infrequent▼(Not frequent; not happening frequently)
adjective
[UK: ɪn.ˈfriː.kwənt] [US: ˌɪn.ˈfriː.kwənt]

rare [rarer, rarest]▼(very uncommon)
adjective
[UK: reə(r)] [US: ˈrer]

sparse [sparser, sparsest]▼(having widely spaced intervals)
adjective
[UK: spɑːs] [US: ˈspɑːrs]

thin [thinner, thinnest]▼(of low viscosity or low specific gravity)
adjective
[UK: θɪn] [US: ˈθɪn]