(obsolete) An awkward or foolish person. / (obsolete, regional, England) A snail; a snail’s shell.

Alternative spelling of tatty (“woven mat or screen”)

(physics) a device that absorbs radiant energy and converts it into electrical energy

(logic) Alternative form of ∧, the conjunction operator. / (logic) The binary operator and, only true if both of two inputs is true. In infix notation.