Mots rares et à high-score au Scrabble

An Arabian shrub (Catha edulis) whose leaves are chewed as a stimulant; one of the few Q-without-U words legal in tournament play.

A type of rough, blocky basaltic lava flow; one of the highest-value two-letter plays because it lets you place an A alongside a Q or Z.

The vital life force in Chinese philosophy; the single most important two-letter word in tournament Scrabble because it lets you play a Q without a U.

The 14th letter of the Greek alphabet; a 9-point two-letter word that places an X next to an I — essential for parallel plays.

A small wallaby-like marsupial from Western Australia; a 24-point word that pairs a Q with a K, valuable for tile-heavy racks.

A brilliantly coloured Central American bird (and Guatemala's currency unit); a 7-letter bingo worth 25 points that uses both a Q and a Z.

A Sufi Islamic devotional act of repeated remembrance; a 13-point word that pairs a D, H and K with no vowels between them.

An exclamation used to express that one feels cold; a 4-letter word with no vowels at all, worth 6 points and a useful dump for a B-heavy rack.

A coin-operated record player; a 7-tile bingo packing a J, K and X that clears the rack for a 77-point opening move plus the bingo bonus. Valid in five languages' dictionaries.

The accumulated stakes in a game won at once; a 7-tile bingo using a J and a K that opens with 72 points including the bingo bonus.

A loose garment covering the whole body worn by some Muslim women; a 5-letter Q-without-U word worth 16 points and valid in three languages' dictionaries.