FIR

n. a tall evergreen tree with needles and cones that stays green all year.

n. a coniferous evergreen tree of the genus Abies, characterized by flat needles and upright cones.

“We walked through a forest of tall fir trees covered in snow.”

“The hillside was densely populated with silver fir, providing a stark green contrast against the grey granite peaks above.”

n. the wood that comes from a fir tree, often used for building.

n. the timber or wood derived from fir trees, typically used in construction or paper pulp production.

“The cabin was built entirely from local fir and pine.”

“The carpenter preferred working with fir for the internal framing due to its straight grain and relatively high strength-to-weight ratio.”

n. Stands for Flight Information Region.

n. Abbreviation for Flight Information Region; a specific volume of airspace where flight information and alerting services are provided.

“The pilot contacted the London FIR as the plane crossed the coast.”

“As the aircraft transitioned between the two FIRs, the crew noted a slight discrepancy in the reported altimeter settings from the respective controllers.”

Technical

adj. Stands for Finite Impulse Response.

adj. Abbreviation for Finite Impulse Response; describing a filter whose response to any finite length input is of finite duration.

“The engineer used an FIR filter to clean up the audio recording.”

“The system designer opted for an FIR filter to ensure linear phase characteristics, despite the higher computational cost compared to recursive alternatives.”

Technical

n. Stands for First Information Report.

n. Abbreviation for First Information Report; a document prepared by police in certain countries after receiving information about a crime.

“The victim went to the police station to file an FIR after the robbery.”

“The magistrate noted that the details in the FIR were inconsistent with the testimony provided by the primary witness during the preliminary hearing.”

Dialect · Formal