What does 'double strain' mean?

Double straining means pouring the cocktail through both a Hawthorne strainer (the wire-coiled one fitted in the shaker) and a separate fine-mesh strainer held over the glass. It removes both large ice shards and small bits of fruit, herb, or citrus pulp.

A standard cocktail strain uses only the Hawthorne strainer — the metal disc with a coiled spring around the edge that fits inside a shaker. The Hawthorne keeps cubed ice in the shaker and lets liquid pass. A double strain adds a second filtering layer: a small handheld fine-mesh strainer (sometimes called a 'tea strainer' or 'conical strainer') held over the serving glass while you pour. The fine mesh catches the small ice shards, broken-up citrus pulp, muddled herb fragments, and egg-white speckles that the Hawthorne lets through. Double-strain when the drink is served up in a coupe or martini glass and you want a clean appearance: Daiquiri, Sidecar, Cosmopolitan, Whiskey Sour. Do NOT double-strain drinks where muddled fruit or herbs are part of the texture (Mojito, Smash, Caipirinha). Equipment cost: a fine-mesh strainer is under $10 and outlasts most other bar tools.