Word Study
titmouse
CIDE DICTIONARY
titmouse, n. [OE. titemose, titmase; tit small, or a small bird + AS. māse a kind of small bird; akin to D. mees a titmouse, G. meise, OHG. meisa, Icel. meisingr. The English form has been influenced by the unrelated word mouse. Cf. Tit a small bird.].
Any one of numerous species of small insectivorous singing birds belonging to Parus and allied genera; -- called also tit , and tomtit . [1913 Webster]
" The blue titmouse (Parus cœruleus ), the marsh titmouse (Parus palustris ), the crested titmouse (Parus cristatus ), the great titmouse (Parus major ), and the long tailed titmouse (Ægithalos caudatus ), are the best-known European species. See Chickadee ." [1913 Webster]
OXFORD DICTIONARY
titmouse, n. (pl. titmice) any of various small tits, esp. of the genus Parus.
Etymology
ME titmose f. TIT(1) + OE mase titmouse, assim. to MOUSE
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