Loo, or lue, is subdivided into limited and unlimited loo, is a game the complete knowledge of which can easily be acquired; it is played two ways, both with five and three cards, though most commonly with five, dealt from a whole pack, either first three and then two, or by one at a time. Several persons may play together, but the greatest number can be admitted when with three cards only.

After five cards have been given to each player another is turned up for trump; the knave of clubs generally, or sometimes the knave of the trump suit, as agreed upon, is the highest card, and is styled pain; the ace of trumps is next in value, and the rest in succession as at whist. Each player has the liberty of changing for others, from the pack, all or any of the five cards dealt, or of throwing up the hand, in order to escape being looed. Those who play their cards, either with or without changing, and do not gain a trick, are looed; as is likewise the case with all who have stood the game, when a flush or flushes occur; and each, excepting any player holding pam, of an inferior flush, is required to deposit a stake, to be given to the person who sweeps the board, or divided among the winners at the ensuing deal, according to the tricks which may then be made. For instance, if every one at dealing stakes half-a dollar, the tricks are entitled to sixpence a piece, and whoever is looed must put down half-a-dollar, exclusive of the deal; sometimes it is settled that each person looed shall pay a sum equal to what happens to be on the table at the time. Five cards of a suit or four with pam, compose a flush, which sweeps the board and yields only to a superior flush, or the elder hand. When the ace of trumps is led, it is usual to say, "Pam, be civil;" the holder of which last mentioned card is then expected to let the ace pass.

When loo is played with three cards they are dealt by one at a time, pam is omitted, and the cards are not exchanged, nor permitted to be thrown up.