Let's take a look at Xiaobo Li's thesis : PHYSICAL, CHEMICAL, AND MECHANICAL PROPERTIES OF BAMBOO AND ITS UTILIZATION POTENTIAL FOR FIBERBOARD MANUFACTURING, May, 2004
"As a cheap and fast-grown resource with superior physical and mechanical properties compared to most wood species, bamboo offers great potential as an alternative to wood." (p. 2)
"The chemical composition of bamboo is similar to that of wood." (p. 5)
"The lignin values of 20-26% place bamboo at the high end of the normal range or 11-27% reported for non-woody biomass [Bagby 1971] and closely resemble the ranges reported for softwoods (24-37%) and hardwoods (17-30%) [Fengel 1984; Dence 1992]." (p. 21)
"Unlike wood, bamboo has no secondary growth; all gains after it reaches its full height are due to the addition of material to cells after the first year." (p. 28)
Although it's a grass and not a tree, bamboo is a wood-like material.
It "is also one of the oldest building materials used by human kind [Abd.Latif 1990]." (p. 1)
Yet, it's not part of the European construction rules for now.
Anyhow, with regard to its properties, the material obtained from bamboo can only be classified in the timber category of the Eurocodes.
When talking about construction, bamboo is wood.